There are also places like CTRL+Paint which are 100% devoted to providing tutorials for digital painting and rendering (there's also CG Cookie but you typically have to pay for their tutorials and lessons. that will give you some great tips and techniques for painting in general. even if it's not the subject matter you're looking to paint will get you some awesome tutorials from Tumblr, DA, etc. Even just searching specific tutorials like 'painting skin', 'painting hair', 'painting backgrounds', etc. I think my best piece of advice for this would be to look up some tutorials. Some people end up having 2 or 3 copies of the illustration as separate layers for things like color dashing and lighting rendering, others don't even shade and only use flat colors.

Some people use masks, whereas others use clipping groups and locked layers. Some people color over the original sketch. This can seem like a daunting challenge at first, but it means that no matter what skill level you're at, with a bit of practice and experimenting, you're bound to find a method, technique, and style that works for you. The best part about coloring digitally is there are so many ways to do it.

Soft cel shading firealpaca tutorial