The shading is where the image really starts to take shape. For each flat base color, I add darker areas where things would be in shade, so every color ends up having two tones. I know some artists do a third tone on everything for a highlight color. Personally, for reasons of time management, I just stick with the shadow areas and forego the highlights. I usually only do highlights for certain effects, like shiny materials, reflective surfaces, or rim lighting.

This is also the stage where I’ll use a few gradients here and there to add a little variety to the shaded look. I try not to go overboard with the gradients and blending, since I really do like that clean and cartoony, cel-shaded look. But for something like sky, a gradient works really well in conveying that transition to haze at the horizon.

Next up, mist effects…