I made myself use colors I really don't like: lime green, orange, and other such colors. I had to force myself to buy them. Guess what? After that I had no problem using different colors because that quilt was awesome. It was a child's quilt because it was easier to start with.
I also used my EQ when I taught a beginning quilting class so students could have a line drawing of their quilts and then color them in. Each one used different colors and all turned out great.
Going to quilt show also helps. You can see how others use color and scale of print to make their quilts. and ... of course you might see some quilts that absolutely turn you off. Going over what you like and don't like about the quilts will help you a lot. Just, please, if you don't like a quilt keep your opinions to yourself so you don't hurt someone's feelings.
ali