I just did a week long class learning comic art and cartooning with Matt Maley, who is a really great comic artist who used to work at Marvel! This was the cover I made for my comic, Flash B and Speed Rume!
This shows the different stages (below). First, the sketch, then the 'inking in,' and finally adding color with markers and colored pencils.
Jojo did the class too. This is her comic.