This is a guest post written by Vivien from Inspirationbit. You can see the original post here.

Did you know that colour and visual elements activate the right brain (emotions), while the printed words activate the left brain (logic)? Colour and Typography remain to be the two most important elements in design. When you harmoniously combine them all you attract a quicker attention to the subject, reinforce impact and recognition, help in establishing powerful identities and brand, set a mood. Today we examine the DOs and DON’Ts in designing with colour.

Babies are colour-dominant: they are more attracted by colour than form. And even though we generally become more form-dominant as we mature, colour still plays an important role on how we perceive the message. For instance, why does red always call to attention? Whether you want to tweak the colours of your site, or design an ad or a poster to attract people to your products or services, or even paint the walls in your house, these colour essentials should help you in becoming more colour-wise.

DO take time to learn the colour wheel.

All colours are made up of three primaries: red, blue and yellow. When you combine the primaries, you get the three secondary colours: orange, purple and green. When you combine each secondary colour with its neighboring primary, you get six tertiary colours: yellow-orange, yellow-green, blue-green, blue-purple, red-purple, red-orange. That’s how you get the familiar 12-colour wheel.

Every colour has a temperature: from the red/yellow side of the spectrum it’s warm, and from the blue/purple side it’s cool. It has an intensity that’s described as saturation or chroma. Saturation is determined by how much or how little grey a colour contains. High intensity colours are pure, bright and vivid. Less saturated colours are muted, soft and subdued. Every colour has a value, determined by its lightness or darkness. When planning a colour combination, value and saturation are as important as the hue (synonymous with colour).

DON’T miss on understanding the basic colour wheel rules:

• Most colours look great when combined with the shades in various values or intensities. These colour schemes are called Monochromatic, which consist of colours drawn from the same hue.
• Colours also love to hang out with their next door neighbors. Any three neighboing colours on a 12 part colour wheel make up an Analogous colour scheme. They are always harmonious as they share the same undertones: yellow-green, yellow and yellow-orange. To add a bit more impact to the analogous group, you can expand it with another neighboring color, e.g. orange.
• Opposites attracts, even with colours, and that’s how you get Complementary colours: they are the opposite hues on the colour wheel, that “complete” each other when used as a pair. Warm colours have cool complements and vice versa.

I found this handy Flash application that visually explains the colour wheel in an easy to follow style. There’s also a helpful HP colour wheel that showcases different colour schemes.

DO analyze the colour undertones.
If you like blue but want a subtle effect, choose a white or grey with a blue undertone. A red-orange terracotta pot has a yellow tone to it, hence those colours will blend harmoniously with each other. On the other hand, don’t emphasize an undesired undertone by pairing it with its complement: if the shade of brown has a pink undertone to it, combining it with green (the complement of red) will only intensify the problem.

Learn to identify colour tone, its warmth or coolness. A warm blue contains some red that makes it to look more purple, while a cool blue contains some green, which makes it more aqua or teal.

Do keep in mind that neutrals also have undertones. Often people will mistake grey for blue if there’s a blue undertone, or plum if the undertone is violet.

DON’T neglect the fact that colours ‘change’ according to their surrounding:
A large rectangle and a narrow line (or type) of the same colour will seem to have different values when placed against a white background: the colour in the line will look darker than it does in the rectangle, because it’s surrounded by much brighter white space.

When two shades of the same colour, one dark and one light, are paired with each other, the darker shade will look darker and the lighter shade will appear to be lighter: a pink rose will seem to be paler against a purple background.

Larger colour spaces will affect the smaller ones: if a small square of medium yellow is surrounded by a larger area of black, the yellow square will seem to be brighter than when surrounded by white. Any colour will appear lighter against a darker colour and vice versa.

Outlining a colour in a darker shade will enhance the enclosed colour, helping to keep a colour from “spreading” into surrounding areas. On the other hand, a lighter outline will cause a colour to spread to adjacent colours, and reduce the strength of the enclosed colour.

This valuable tip comes from David Airey: There’s also the illusion how dark colours surrounding light ones will make the lighter area appear smaller than it is if it were the opposite (dark surrounded by light). It’s why you should always bump up the text size if you insist on using white text against a black background.

DO explore the colour psychology
While perceptions of color are rather subjective, and have different meanings in various cultures, some colours affect us in a similar way. The human eye sees warm colours before cool hues. Cool colours appear to recede, while warm colours appear to advance, however the degree of saturation can make a difference.

• RED: With its aggressive, stimulating and sexy nature, assertive attention and provoking action, the red is impossible to ignore.
• PINK: Depending on its saturation or value, pink evokes varied mood swings. Magenta and fuchsia are perceived as sensual and theatrical. But water-down the red in lighter pinks and the raw sensuality of red is replaced with gentle romanticism.
• ORANGE: Inheriting some of the drama of red, orange is tempered by the friendly humour of yellow. It’s the colour that stimulates the appetite and radiates with warmth and vitality.
• YELLOW: Yellow and black is the most unignorable colour combination in nature - tigers, stinging bees - it’s the colour that says: you’d better pay attention to me.
• BROWN: Rustic, durable, wholesome and deliciously rich are just some of the traits of the colour that’s often associated with earth and home, substance and stability.
• BLUE: Ever noticed how many corporations and financial institutions use blue in their brands? That’s because blue is seen as dependable and committed. It is also the colour we often associate with calm and serenity. Darken the blue and you’ll add an instant authority, credibility and power to it.
• GREEN: Because of its association with nature and foliage, green in design can be used almost like a neutral colour: greens never clash with red or pink roses, yellow sunflowers, lilacs or bluebells.
• PURPLE: It’s perhaps the most enigmatic and complex colour, with the range of meanings - from royal to elegant to spiritual to mysterious. Purple is often favoured by very creative and eccentric people who are not afraid of appearing daring.
• WHITE: Not surprisingly white communicates purity, sense of clarity and simplicity. White is also perceived by the human eye as a bright colour, that’s why it works so well in contrast with all other colours.
• BLACK: People see black as the most dramatic, heavy, powerful, classic colour with an up-scale look. Because of its extreme contrast to white, black and white is the quintessential combination of depth and clarity, power and innocence.

DON’T be afraid to experiment with colour combinations. Sometimes even the forbidden combinations work. Check out various online colour tools and applications that will help you to chose the right colour combination for your projects.

DO examine other sites and designs to determine which colour schemes are more appealing than others. In one of the upcoming weeks, I’ll be featuring sites that were designed with the excellent knowledge and sense of colour. Meanwhile, browse numerous CSS galleries, bookmark the sites with attractive colour schemes, thumb through the pages of various design magazines, books, not just the ones for graphic designers, but also architectural and interiour design publications, where you will be inspired by the innovative and fabulous colour combinations.

DON’T forget about the readability when combining colour with type. It’s true that we mainly deal with the black type on white paper/page background, and that a black text on a light background is the easiest to read. However, it doesn’t mean that colour and type don’t mix. When used well, colour can add an emphasis to your message. Pay attention to the relative values and saturation of colours when a background colour interacts with coloured type. The contrast between type and background diminishes when their values move closer to each other, and the type becomes less legible. The contrast between the type colour and the background colour must be considerable to ensure that the type remains visible.

John from iLT also gives this valuable advice: “when using reversed out text (e.g. light on dark), it’s often advisable to make the text a little heavier, as the dark background tends to optically reduce the weight of the text.”