After years of practice, we finally come to the point of “Oohhh that how I was supposed to do it, why I didn’t know it before?” Why nobody shared it with me to save my time and sometimes even passion for the painting. How many of us abandon painting just because they think this is not an art, I’m not an artist? How many of us still learning trying to copy someone because we are afraid of letting our creativity go and bloom?
Yes, I’ve learned a lot by reading and attending Pro classes, but that I know for sure, that these tips will motivate and boost the productivity of every beginner, even if You still think that you are not an artist yet.
I suggest you split all 51 tips by groups, as it could be easier for you to follow and pick the area you need advice from right now.
- Learning acrylic painting
- Tips about the painting process
- Tips about canvases and surfaces
- Tips about brushes
- Tips about acrylic paints
All acrylic painting tips at once before we start talking about each of them:
- Experiment first and more than follow instructions
- Be yourself and love what you are doing
- Show your paintings
- Choose a reference
- Start with an easel
- Try different techniques
- Paint over mistakes or reuse the canvas
- Make notes
- Ask questions
- Practice makes perfect
- Use online galleries
- Ger ready for lack of inspiration
- Paint in the right environment
- Use trash bags
- What to wear
- Do a sketch
- Ugly stage
- Paint dark to light
- Paint larger areas to details
- Work quickly
- Step back
- Sign and date
- Take photos at the right time
- Always wait until it dries
- Paint in layers
- Protect your painting
- Use pre-stretched pre-primed canvases
- Use canvas panels and pads for practicing
- Don’t be afraid of paper
- Experiment with surfaces
- Don’t buy cheap brushes
- Start with a simple brush set
- Clean brushes immediately
- Store brushes properly
- Use large brushes
- Buy artist-grade paint
- Don’t buy all colors
- Buy a color wheel
- Use stay-wet palette
- Paint should be always clean
- Use palette knives
- Be careful with water
- How to make paint dry slower
- How to make paint more opaque
- How to make paint dry slower
- How to create texture
- How to make paint more fluid
- Don’t press
- Use contrasts
- Learn how to blend
- Learn how to mix colors
Tips about learning acrylic painting
1 – Experiment first and more than follow instructions
I’m part of many groups on facebook for acrylic painting. And the most often question and recommendation beginners are looking for is “Advice me some good tutorial how to paint …”.
I have nothing against it, we need to have an idea about anatomy if we’re working in realism and other not abstract movements, of shades, of color mixing etc. But believe me, techniques will never replace your creativity.
What I suggest is when you want to paint a dog, try to paint it as you feel first, experiment as you have no guidance and limits to your art, feel this freedom. And then, after trying and experimenting, watch some tutorials or read some step-by-step guide.
Here is the thing, the more our brain see and learn something the stronger this neural connection will be. Sometimes, people who spend 7 years in music school can not compose their own songs AT ALL. But they can easily read notes and play pieces of any difficulty level. The same is painting.
Feel yourself and your creative cravings first, then polish them.
2 – Be yourself and love what you are doing!
To continue with being your first reference – art is the scene where you can be yourself and at the same time whoever you want – magician in some sense. You create, you deliver or message or you heal your traumas – it doesn’t matter, painting is great for all purpose.
It is a proven method for art therapy, but it is also one the most popular hobby in the world – art was in the TOP-10 hobbies and interests in USA in 2020 (30% of people mention it as favourite activity).
Why it is so important to love what you are doing? Psychological studies have proven that loving what you do boosts overall productivity and enhances performance and creativity. People who enjoy what are they doing in life are more likely to be optimistic, motivated, learn faster, and make fewer mistakes.
Can you imagine?
It is not only mental health which is important, loving what you create means don’t judge yourself, don’t compare too much with other artists, don’t evaluate yourself based on their success stories or paintings.
There is no “right” art and you are your roughest critic.
Art is unquestionably one of the purest and highest elements in human happiness. It trains the mind through the eye and the eye through the mind. As the sun colors flowers, so does art color life.― John Lubbock
3 – Show your paintings
Another way to learning and having feedback in healthy atmosphere is to join some Facebook groups for absolute beginners.
Don’t be afraid of sharing your art! The feedback and support of others will motivate you to keep going and boost your self-esteem as an artist.
Be generous in return and you are very likely to meet some new friends there!
These groups are also a great platform to ask questions and see what people recommend.
Share your painting on your personal social media too, to your friends and family. In fact, I’m sure they will be happy to have some of your works as a gift.
Showing your painting is a key to your progress. If you will hide your paintings you will never see the progress and be conscious about real feedback or things to improve.
4 – To start, choose a reference
For some beginners the most difficult part is to start, it seems like we have lots of ideas, videos on Youtube but still struggling with choice.
What I did with my first paintings when I was a kid or when I’ve started new medium, I just pick my favourite photo form travel or I search on Pinterest for a good references of the idea I have in mind.
The static image is better to start painting. If you will print a photo, you can choose in what size you will print it. To have a printed reference in front of you is a real time-saver.
5 – Start painting with an easel
If you are a beginner, it may be useful for you and easier to start acrylic painting with an easel. At the same time, it is possible to paint without it, on the ground or on the wall, especially if you have a large canvas.
If you have a reference and it is your first time of painting, don’t place the canvas horizontally on the table, it will slightly alter all proportion. Use easel and place reference close to you.
6 – Try different techniques
Learning means not only learning how to paint but also discovering which technique and style is yours.
Think about artists you like, why you like them? I adore Pierre Soulage for textured paintings and choice of colors, for how powerful his expositions are. What do I take from it? He was my inspiration for abstract acrylic painting.
Think about other crafty activities you like – sewing, hand made, photography, pottery? How you can combine them or what techniques you can borrow?
For example, a great artist of nowadays, Rebecca Stern use fabric collages on paper with acrylics and it looks gorgeous:
7 – Paint over mistake or scrap the painting you don’t like and reuse the canvas
Mistakes are vital for learning. “Anyone who has never made a mistake has never tried anything new.” – is an absolute truth. Mistakes are markers for progress. Today you make a mistake and in one month you know exactly that you are doing better, because you don’t have same mistakes anymore.
Be grateful and use mistakes. First of all, you can paint over mistake with acrylics easily. They are more forgiving than oil.
To paint over mistake, apply 1-2 layers of gesso, sand it and paint again!
Second, you always have an option to scrap the painting (here is an easy step-by-step guide, be patient, it takes some time), and reuse the canvas for new painting.
And, finally, sometimes, if you leave this painting for a while and come back to it later, you can find it beautiful. I’ve heard a “legend” about pottery, that the first piece you make could be the most beautiful piece you will ever make, but you will appreciate it only over time.
8 – Make notes
Making notes will save your time and money many times through your artistic life. Notes will help you to identify paint brand that cracks, canvas that warp, best brushes or mistakes in varnishing and drying.
It is also important because you can not remember everything. However, paintings are supposed to last centuries, and sometimes you need to maintain them by replacing varnish, for example. Are you sure that in 50 years you will remember exactly how much and what brand varnish you used to be sure this time your painting will not become milky or yellow?
Just buy a simple notebook and write down materials, techniques and experiments you had.
9 – Ask questions or read blogs
I already shared the idea of joining other groups, so don’t be afraid to ask like-minded people what they think. One the typical post in these groups is when a beginner share a painting and say what he/she is struggling with and ask advice.
Another way is to simply google. My blog and many others try to help you find the answer and Google will help you to find the most relevant blog.
10 – Practice makes perfect
The best thing you can do to learn and paint is to be consistent. Paint something regularly, have some inspiration folders on your phone or boards in Pinterest, try something new or work on something that you want to improve, but be consistent.
Yes, we all know about 10 000 hrs rule, but you don’t have to spend 4 or 5 years to master 10 000 hours of painting and to become an artist, you need to do it on regular basis and with love to stay creative.
11 – Use Artfinder or Saatchi Art to sell your art
When you will have at least 15 works, sign up and create a profile on Artfinder and Saatchi Art. They are popular online galleries where artists of all styles and levels can sell they art safely.
The process of application is not complicated, but you need to have good photos and motivational letter.
12 – Be ready for lack of inspiration
Sometimes we feel like we are not creative at all. It is normal and inspiration depends on our stress level and many other factors. And sometimes we are just tired of what we are doing, not only art.
You can either push yourself and get nothing because it will only lead you to irritation. Or you can admit it and let it be without stressing yourself even more.
As I said stress blocks creativity. We all have friends, loved ones, family, jobs, and something is always happening. Sometimes we feel like it is not the right moment for art. It could be it.
Tips about the painting process
13 – Paint in right environment
Paint, canvas, and finished painting are sensitive to environmental factors like temperature, humidity, and airflow.
High humidity (50%+), low temperature ( below 65F (18C)) will slow down the drying of acrylics.
Dry and hot air will make acrylic paint dry faster or even too fast that can lead to cracks.
The air should never blow directly on the painting. It will affect the drying process or even ruin the painting..
Ideal environment for painting is 65-75 degrees Fahrenheit (18 – 24 C), 50% humidity and well aired room.
14 – Use trash bags to protect floor
A cost effective way to protect the floor or walls and other surfaces is just to cut big trash bags and fix them with duck tape. You can easily organise the workplace in few minutes and then fold the plastic and reuse it later.
If you have tiles on the floor, it can be fine, You can clean it right after you finish painting and it will be pretty easy, because acrylic paint doesn’t adhere to tile. But if you have wooden floor and you will let paint drip on it, you will be unable to save the floor after, because wood soaks paint.
Acrylics are quite hard to wash off from clothes and fabric, so you can protect with trash bags even your couch.
15 – Wear something to paint
Acrylic paint is pretty hard to wash off from clothes so try to wear something that you will not regret and you feel comfortable to move and paint.
Don’t be afraid of paint on your skin. Modern formulas are non-toxic and easy to wash off. Still better not to use acrylic on the skin, it is not supposed to be used this way and still contain agents and chemicals.
16 – Do a sketch
For beginning in painting better to do a sketch, especially if you paint landscapes, portraits or nature morte. If you do abstract art you can also, surprisingly, need a sketch, if you have a specific idea – to “try” it.
You can slightly do it with a pencil, trying to place objects on the canvas. Don’t go deep into details, just the overall composition.
17 – Ugly stage
Painting teaches you patience. A sketch and first large strokes of darker color easily demotivate some beginners. You are right, it will look nice sometimes soon. Turn on your imagination and be focused on painting, you don’t judge a cake by the appearance of the dough.
18 – Paint dark to light
The golden rule of painting is to paint from dark areas and colors to light details. It means that you start with main darker color, you do the background and then you move to the mid-tones and in the end you add shapes and highlights with light colors.
It allows you to create depth, but also it has a practical reason – it would be hard to shape light objects with dark colors and to control the thickness of each layer.
It is also what can differ beginners from pros. How they create shapes and shades.
19 – Paint from larger areas to details
Pairing with previous tip – it is easier and smarter to paint from larger areas and objects to smaller ones. Create a background, then move to lighter and detailed image and create smaller objects and shapes.
Larger areas are usually darker. But details can also make accents with light or very dark colors.
20 – Paint quickly and be decisive
Acrylics are fast-drying and you will get used to them over time. Based on it, you need to move your brush quickly enough and be very sure about what you are doing. The first time, just think less and do, after you can analyze your strokes.
Sketching will help you navigate.
21 – Step back to look at the painting
Like a real artist from movies, you need to step back. It is important to have an overall view, to see the whole composition from time to time.
22 – Sign and date
Yes, even you don’t still believe in yourself, you are already an artist, sign your work. And put a date on the back, plus, mention mediums (acrylics on canvas, e.i.).
You can sign you painting on the back or in the corner on the painting itself. Choose your signature wisely, it should be something permanent, that you will use for years. Plus, it should be something to help people identify your work.
A first name or initial and last name usually work.
23 -Take photos before applying isolation coat or varnish
Great photo can be not a case if you want to take photo of a finished and varnished painting, simply because the protective finish is usually glossy.
What you need to do is to remember that you take photos when the finished acrylic painting is fully dried, BEFORE isolation coats or a protective finish.
24 – Always wait until it dries
Drying process is extremely important to follow.
Acrylic paint is fast-drying and still it is fully dried, normally, in 24 hrs., except if you thin it, use retarders or open acrylics. If so, you need to wait longer.
And not only when it is done, but, ideally between all layers: between gesso layers you need to wait as much as the manufacturer asks you (read the label), between paint layers (thin layers dry faster), before applying isolation coat and before the protective finish.
Be patient, changes in dry time and shifts in dry time between layers will result in paint cracking or even peeling off.
Remember that thick layers, paint with retarders will dry slower, thin layers will dry faster. In general, acrylic paint dries in 10-20 minutes to touch.
25 – Paint in layers
We like acrylic painting because acrylics are fast-drying and you can paint over faster. This is why acrylic painting is a painting of layers: we are moving from under painting, from background layers to top, detailed ones.
Acrylic painting is like a cake: we prime a canvas, then we put first layer, second, third and so on. As we discussed, usually we go from darker to lighter colors and from larger objects to small details.
26 – Protect the painting
Acrylic painting can last centuries and it all depend on how well it was protected and maintained.
The full protection process needs knowledge and attention, but you will get used to it:
- Prime your canvas or use pre-primed canvas
- Once your painting is done and fully dried, apply an isolation coat to seal the surface and protect it from damage
- Once isolation coat is dried, apply varnish or protective finish to protect and seal your painting for the next 50-100 years,
- If you want, place your painting under a glass or UV-protected sheet with framing to protect from fading and dust
- Maintain properly: store in well-aired not too cold or warm areas, with 50% humidity; clean regularly, avoid touching it.
The full protection guide is here with detailed explanation, links and how-to guides.
Tips about canvases and other surfaces
27 – Use pre-primed pre-stretched canvas
There are 2 main fabric for canvas: cotton and linen. Basically, they come raw in rolls and artists stretch them and prime them in the studios.
That how it was before, and this is the way how almost all professional artists do it now. However, the best way to start for a beginner is to buy online or in an art supplies store a pre-stretched and pre-primed (triple primed is the best option) cotton canvas.
Linen canvases will be more expensive and a beginner (and some pros, to be honest) won’t be able to tell the difference sometimes.
Stretching a canvas is a separate skill, you will master it, but don’t start with it. Saggy canvas will ruin all joy.
Priming a canvas is crucial because a primer prepare a canvas to paint, increase paint adhesion and makes the surface smooth and easy to paint onto. The most common primer is a gesso.
An affordable option with 3 layers of gesso, good stretching, and nice reviews is Blick Premiere Cotton Canvas. Recently, I reviewed about 38 good canvases for beginners and made the TOP shortlist, you can read about it here.
28 – Use canvas pads or panels for practice
Sometimes we are too scary to paint directly on the canvas. Well, nothing wrong with it, you can use acrylics on canvas panels and paper or canvas pads. It is a cheaper option for practicing.
Panels are cotton or linen fabric glued to a board and are quiet hard to hang. Pads include usually 10-20 paper sheets which are very easy to frame if you want.
Mont Martre Canvas Panels and Canson XL Paper Pad.
More details about what is it and what are other alternatives fell free to read in related article.
29 – Don’t be afraid of paper
There are special paper and paper pads for acrylic paint. This paper is thicker and rougher than a normal one and has a canvas-like texture.
You should be careful with water, because paper soak water easily and will warp. But still paper is a great surface to practice and create smaller sketches for larger paintings.
It is also a portable option and extremely cheap. Canson XL Paper Pad costs 9 dollars for 24 sheets, which means 0,40 cents per sheet. Very affordable.
30 – Paint on diverse surfaces
Anything that acrylic paint can stick to, you can use canvas, paper, wood, fabric, plastic, metal, glass, etc. All surfaces need special preparation and sometimes specific paint. But you definitely have a lot of places to be creative.
Tips about brushes
31 – Don’t buy cheap brushes
First of all, you don’t need all brushes of the world to start painting. But also, don’t be teased by the cheapest option. The quality of all materials is very important.
A cheap and low quality paint brush will leave brushstrokes and bristles everywhere.
For acrylic we use synthethic brushes.
32 – Start with a brush set
The best way to start is to buy a set of synthetic brushes, get one really large, one for detailed work (a thin brush with long bristles), one round, one flat. Of course, you can have as many as you want, but these will help you with any kind of painting ideas.
Filbert brushes (flat with an oval top) are good to start with. You can buy different sizes: small, medium and large.
Good brush sets are Catalyst Polytip Bristle Long Handle Brush, Set of 4 and Blick Wonder White Set – Assorted Handle, Set of 6. The cost per set for beginners will be from $20 to $50.
Over time you will understand better what kind of brush you need.
33 – Clean brushes right after your painting session
Pretty obvious but still very true. If you forget to clean brushes right after you’ve done painting, you will lose a lot of brushes and their quality will degrade.
Use 2 jars with water during painting to keep brushes clean and a special towel to dry them quickly. I use an old piece of towel.
How to clean brushes after acrylic painting:
- Use mild soap and water to clean brushes.
- Lay your brushes flat to dry. We don’t let water destroy the glue in the ferrule and loosen the glue.
- Store them bristles up.
Never leave your brushes in water for long time.
34 – Store brushes properly
Use a separate jar or glass and store all brushes only bristles up, otherwise, the bristles can bent.
Store brushes only when they are clean and dried. Store brushes for varnish separately and sign them.
35 – Use large brushes and wide strokes
WIth a larger brush it is easier and faster to cover any areas. It saves time and create less brushstrokes on the canvas (if your brush leaves them).
Wider strokes are perfect for backgrounds, thin strokes – for details. Professional artists can create all kind of shades and details with wide strokes.
Tips about acrylic paint
36 – Buy artist-grade paint
Same as for brushes and other materials – don’t go with the cheapest. Try to find the best price-quality option.
There are 2 grades of the acrylic paint: student and artist. They differ by quality and composition. Artist grade is better, contains more pigments and can be more expensive, but it is the real paint artist will use for painting that will last centuries.
Normally, you can tell by brand, price, and name if the paint is artist-grade. For ex., Artist’s paint or Studio paint.
37 – Don’t buy all colors
You don’t have to buy big jars and lots of paint to start. First of all, it’s expensive. Second, you can learn to mix colors.
Red, blue, yellow, black, white, and burnt umber – good paints to start painting.
All good brands have basic sets of paint. Good paint brands are Golden, Liquitex, Winsor&Newton, Pebeo, Utrecht, Amsterdam, etc.
Golden has a good artist-grade set of 6 colors: Benzimidazolone Yellow Medium, Carbon Black, Phthalo Blue (Green Shade), Phthalo Green (Blue Shade), Quinacridone Magenta, and Titanium White.
38 – Get a color wheel
A color wheel is basically a circle with colored sections representing the relationships between colors. Main colors and the color spectrum changes.
By the way, did you know that Newton invented color wheel?
Why you should use it?
- first of all, you can learn how to mix colors
- you will also learn how the same color will look like if you mix it with white or black
- you can also buy a black-and-white color wheel to learn color mixing
- to learn what colors contrasting with each other
A color wheel is normally easy to find and purchase in every art shop or online.
39 – Use stay-wet palette
Acrylics are fast-drying, and when you squeeze more paint than you will use on the palette, it will dry and you won’t be able to reactivate it again.
You will learn with experience how much paint you need, meanwhile, use stay-wet palettes.
A Stay-wet palette is a palette for paint which keep them wet and slows down the drying process. You can easily make one at home: get a container and paper towel, soak them in water, and Voila!
You have more time to work with paint, you have less dried and ruined paint – save time and money!
40 – Paint should be always clean
When you’re painting, you dip a brush into water and into a palette or directly in paint (do not recommend this).
To keep the paint clean, use one container with water only to wet brushes and another one to clean them.
41 – Use palette knives
Palette knives have different shapes and sizes, but the most common one looks like this:
I adore them and to be honest use them more often than brushes. In general, you will use a palette knife for mixing colors on the palette, because a brush can mud colors while a palette knife is easy to clean and mix paint better.
You can also use a palette knife to create an interesting texture – this is how I create my painting.
You can apply thick layers with sharp movements, you can scrap with palette knife or you can create an even and smooth surface. Experiment!
42 – Be careful with water
Avoid tap water and especially using too much water. Water destroys paint, to be more specific, water dissolves paint composition, and agents in paint, binder, can’t stick to each other. This means the paint will not last as long as it could and can eventually peel off.
If you use water, try to avoid tap water and use distiled water instead.
If you don’t have any other mediums to thin the paint, do not add more than 30% of water. Acrylics don’t work as watercolor.
I need to mention, that there is one way to use more water – it is when you want to create a wash – adding water to the color we create a semi-transparent layer of this color and it can be a background.
Beginners should be very careful with water.
43 – To make paint dry slower
For a beginner fast-drying properties of the acrylics can not be fun, you have 10-20 minutes to finish the layer. The good news is that we have a lot of ways to slow down the process and have more open time – more time to work with paint.
Drying process of acrylics is a simple evaporation. To make them dry slower, we need to slow down the evaporation, to keep water in the paint or to use special paint, with longer workability. Finally, we can use special mediums that were created to make acrylic paint dry slower.
- use a retarder like Golden Acrylic Retarder or Liquitex Slow-Dry Medium, to check more alternatives, read the full article about slowing down the drying process
- paint in higher humidity or in a dark cool room or even basement
- use Golden Open Acrylics – this paint stays wet for up to 1 hour!
- mist the back of the canvas
- use a stay-wet palette or spray your normal palette with water
- using Liquitex Palette Wetting Spray
One of these tips will absolutely be enough to help you keep your paint wet longer and make acrylics dry slower.
44 – Tips to make the paint more opaque
Student-grade paint is less opaque than artist paint. Opacity means how much light goes through this color. In practice
To add opacity to the paint, you can:
- Add Titanium white, as it is the most opaque color, but note that it will affect the tint too.
- Apply an underlayer of titanium white
- Mix colors, e.i. orange is more opaque when you mix it than when you use an orange color from tube.
- Choose another, artist-grade, paint
If you need more understanding of the opacity/transparency and an explanation about 7 ways to make the paint more open, check this post.
45 – How to make the paint dry faster
Some of you may be too impatient or may put much effort to make acrylics dry slower than now it is annoying. If you really think that you need to speed up the drying process, the easiest way is to use a hairdryer.
Don’t direct it straight on the painting, don’t turn on the max power, avoid using hairdryer too long. First of all, remember that any shifts in dry time between layers or areas on the painting can lead to cracks.
There is no special fast-drying mediums because acrylic paint itself is very fast-drying.
If you don’t want to use a haidryer or a heater, you can also place the painting in the dry room.
46 – How to make the paint more fluid
The process of thinning acrylic paint, makes it more fluid and easy to work with.
The easiest and most effective way is to buy a flow improver, like Liquitex. The process is simple, adding the medium check the consistency of the paint. If it is thin and fluid enough, start painting. If not, add a bit more.
Please, don’t add too much water, water is not only thinning the paint, but destabilizing its composition.
THe thinning process itself is an important step in learning, please read this article to understand what is the composition of the paint and why water is not the best option.
47 – How to create texture
Acrylic paint can be applied thin and thick. Thicker application and using palette knives or sponges, or even other materials and mediums can create textures and fantastic effects.
First, don’t add water at all – the paint will be very thick and you can use a palette knife to apply it directly on the canvas.
Another way is to use your fingers – you can create strokes, lines, prints
48 – Don’t press too hard
Never put too much pressure on brushes or canvas, canvas is stretched and the shifts in stretching can lead to sagging, which means your painting is damaged.
Painting details try to be as light as possible, but still very decisive!
49 – Use contrasts
Using color wheel you can discover what colors contrast with each other. Warm pigments like red, orange, yellow will create a contrast with cool pigments – blue, green, purple.
Bright accents and contrasts attract people and make your painting something to remember.
Contrast is the best way to make your paintings visually interesting and to add a realistic look. You can do this by using warm colors (reds, yellows, oranges) next to cool shades (blues, purples, greens).
50 – Learn to blend
Blending is “mixing” colors directly on the painting to create a gradual and smooth transition.
It will take some time, but you will definitely get it. Once you know how to blend, your backgrounds will be perfect!
You can use the wet-into-wet technique – blend the colors together while they are still wet or mesh the colors right on the canvas.
51 – Learn to mix colors
This is the last but probably one of the most important tip you should know. Mixing colors and being able to understand it and mix them by yourself – it is kind of creative freedom.
It is also the question of saving money, quality – as we discussed some colors are more opaque when you’re mixing them by yourself, and variety – now you can create so many tints! Professional artists are more likely to mix all colors they need by themselves.
You can learn to mix any color from the 3 basic colors: red, blue, and yellow. They are primary colors, which means you can not create them by mixing other colors.
There are also secondary colors – the colors you create by mixing 2 primary colors:
If you mix 1 primary color with an equal amount of 1 secondary color, you create a tertiary color:
By mixing colors again and again you will create other tints. Make swatches to keep results and take notes to know exactly what to mix next time!
You should also know how to combine colors on the painting, each color has a complimentary one (the color on the opposite side), e.i. for yellow purple is complimentary.
Swatches will also help you to discover that some acrylics dry darker. Usually, the cheaper paint is, the bigger can be that difference and “surprise”.