How to choose colours in advertising projects?

Colour is the first thing the human brain registers on a poster, flyer or business card - before it even reads the first word. Chosen well, it works like a quiet salesperson: it builds mood, guides the eye, hints at what the message is about. Chosen badly, it tires the eyes or sends a completely different signal than you intended. The good news is that choosing colours can be learned - and you do not need to be a graphic designer to do it sensibly.

Basics: the colour wheel, warm and cool, dominant plus accent

All colour theory comes down to one simple tool - the colour wheel. It is a circle with every colour arranged around it. Colours next to each other (for example blue and green) are related and work in harmony. Colours opposite each other (blue and orange) are contrasts - together they shout and grab attention, but used without restraint they can tire the eye.

We also split colours into warm and cool. Warm ones - red, orange, yellow - suggest energy, movement, closeness; they seem to "step forward". Cool ones - blue, green, violet - calm things down, add distance and professionalism, as if "receding" into the background. The choice between warm and cool alone sets the tone of the whole project.

The simplest rule of good composition is dominant plus accent. One colour rules and takes up the most space, while a small, strong accent guides the eye where you want it - to a button, a slogan, a QR code. If everything shouts equally loudly, the eye has nowhere to rest and the whole thing blurs into chaos.

Colour psychology: associations, not rigid rules

Colours carry associations - worth knowing, though not treating as unbreakable laws. The reaction to a colour depends on context, industry and even culture (white means purity in one place, mourning in another). Below is a short, calm cheat sheet of the most common associations in our cultural circle.

• Blue - trust, calm, solidity. Readily chosen by companies, banks and medical services.
• Red - energy, passion, urgency. It draws the eye and stimulates; it works strongly, but in large amounts it can overwhelm.
• Green - nature, health, freshness, balance. A natural choice for eco, food and wellness.
• Yellow - optimism, joy, warmth. It brightens beautifully, but as a text colour it can be hard to read.
• Black - elegance, prestige, class. It builds a premium feel, especially with a little empty space around it.

The point is not to pick a colour "because you have to", but to check whether it fits what you want to say. An aesthetic medicine clinic and a car workshop speak different languages - and their colours should speak differently too.

How many colours: less means better

The most common beginner mistake is too many colours. The wish for a design to be "cheerful and varied" ends in a fairground where nothing stands out. The proven rule is a limited palette - and sticking to it consistently.

• Main colour - the foundation of the whole design, the shade people will associate with the brand.
• Supporting colour - backs up the main one, fills backgrounds, sections and secondary elements.
• Accent - one strong colour for the most important things: a slogan, a button, a call to action.

Add to that neutral shades - white, grey, deep black - which create "air" between colours and let them breathe. Three colours plus neutrals is usually all you need for a design to look clean and professional.

The most important thing here is consistency with your brand identity. If you already have a logo, brand colours or a website, a new flyer, poster and business card should play the same shades. A client who sees your colour for the fifth time starts to recognise it - and that is the whole point of a brand.

Readability: contrast and eye comfort

The most beautiful palette is useless if the text cannot be read. Readability is decided above all by contrast between text and background. Dark text on a light background (or the other way round) reads effortlessly. Light text on a light background, or dark on dark, is the quickest way to make the reader simply give up.

• Give important content strong contrast - the more important the message, the more clearly it should stand out from the background.
• Avoid irritating combinations, such as pure red on pure blue - the eye vibrates and does not know where to focus.
• Remember people with weaker eyesight - good contrast is not a fancy extra, just plain accessibility.
• Thin, light text on a coloured background often "disappears" in print - better to give it more weight or a darker background.

A simple test: squint and look at the design. If the text still stands out and it is clear what matters most, the contrast is fine. If everything blends into one blur, it needs to be strengthened.

Colours and print: why the screen lies

Here we reach the crux that is easy to forget: a monitor shows colours differently than paper. A screen emits light and mixes colours in RGB mode (red, green, blue). Print lays ink on paper and works in CMYK mode (cyan, magenta, yellow, black). These are two different worlds - some of the intense, glowing shades from the screen simply have no equivalent in ink and will come out calmer once printed.

That is why, when designing for print, it is good to think in CMYK from the start and not fall in love with neon colours that will fade on paper. Colour profiles and a proof help here - a test print or preview showing how a colour will really behave on the press. It is the most reliable way to avoid the "but it looked different on the monitor" disappointment.

The paper itself also affects the final effect. The same file on glossy paper gives livelier, deeper colours, while on matte paper they come out softer and more muted, because matte absorbs part of the light. It is worth thinking about this at the design stage, especially with photos and strong backgrounds.

We break this whole topic down in separate posts - do take a look if you are preparing a file for print: which colour mode to choose for print and why colours in print differ from those on the monitor. You will find concrete steps there on how to prepare a design without surprises.

Tools and testing your palette

Luckily, you do not have to choose colours purely by feel. There are simple tools that suggest matching combinations and help you build a coherent palette.

• Palette generators - you start with one colour and the tool proposes matching shades and harmonies from the colour wheel.
• Contrast checkers - you enter the text and background colour, and the program tells you whether it can be read comfortably.
• Preview on different devices - the same design can look different on a phone, a laptop and a printer; it is worth checking on several screens.

The best test, however, is a proof print. Before the whole production starts, see the colours on the target paper with your own eyes - no monitor will reproduce it a hundred percent. A proof print can be ordered for packaging, booklets and disc prints, and for a flyer or poster the option is file verification by our designer. If you are unsure how to prepare the file, we guide you step by step in our guide on preparing files for print.

Choosing colours is not black magic - it is a few simple rules plus a touch of feel that comes with practice. Start with a limited palette, stick to your brand colours, watch the contrast and remember that a screen is not paper. That is enough for your advertising designs not only to look good, but above all - to say what you want them to say.