I usually find that it is easier to colour a drawing if the image is more on the dark side with lots of tones. The technique I use is to apply colour over the tones so as not to destroy the pencil work... a bit like photograph tinting.

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First consider how your final image is going to be used - printing (300 dpi) or multi-media / web (72dpi). This will help you balance the file size and amount of computer memory you will need to create the image. This scan is 72dpi in RGB colour mode at 505x770 pixels in size.

In Photoshop create a new layer and make a basic colour swatch of the colours you are likely to use. This example shows 4 flesh tones, 2 mouth tones, 2 eye tones and 2 hair colours. Use the Eyedropper tool to select these colours when needed.

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