Colour Wheel – A visual representation of the colour spectrum
An artist should know the colour wheel and how the colours of the wheel work together. The colour wheel is made up of primary, secondary and tertiary colours. The three primary colours can be used to make up any other colour on the wheel.
For instance, yellow and blue are used to make green. There are several ways to create green, such as overlaying blue and yellow over the top of each other, mixing them together or using many tiny dots side by side, so that it tricks the eye into seeing green.
Test these methods on a spare piece of paper to get a feel of which colours you'll make when mixing two colours together.