Whenever I mention I'm a Colorist people tend to think I whip out the Crayola's and go to town. While that would be amazing, that's not exactly how it works.
Coloring, is when you're given a b&w piece or layout, and you paint over it. For backgrounds, it's almost like matte painting.
Below are some examples of befores and afters. Have fun!
TMNT FF / BTTS Line Art BG Design: Keith Conroy - Denny Fickle - Chris Palesty