But it gets harder than that. Like in some sigs, the middle part of everything is the brightest. I usually shade the bottom of everything the darkest, but for example, the mammoth in my picture. I only shaded from the bottom up, going slightly lighter in color til I got higher up. Seems like the really good artists don't do it that way. Hes kinda close. Do what he said with a cube, a sphere, a cone, and every other type of 3d shape. Then shade it according to what shape it is. Its kinda like drawing. If you can draw any shape, you can draw anything. The mammoth is a kinda circlular shape, So I would shade it more like a circlular oval. Then depending on the perspective, you would shade shadow where the light would be blocked.