This is the cleaned up rough of my self-portrait avatar. I sketched this digitally. With this character/mascot design workflow, I start with the rough.
The sketch is refined in Photoshop and carried over to Illustrator for "finessing". This is the lineart stage.
I think too many people go straight to coloring without getting their lighting down.
I firmly believe that if you don't get your lighting down properly, you're going to struggle during the coloring phase.
Some folks would say that taking the time to do this messes with their creativity and that may be true for some people. But I relax more knowing I have a guide, albeit rough, to aid me in the coloring process later. Also I said "aid". I don't believe that the guide is cast in stone. You may even notice that while the image looks like it's going to have detailed areas of tone, I simplify it as much as I feel when I get to coloring.
Well this pretty much speaks for itself. Coloring is completed in Illustrator.
I still like to experiment with the details of my coloring technique, but I'm getting close to an all-around method that works for me in terms of speed while maintaining quality.