newbie at colored pencils :<

[xNatje]

I'd suggest starting your drawing with the colored pencils, and not with graphite pencils. This will cause that the linnes will blend more into the whole drawing.
colored pencils over graphite will cause that you can't erase the graphite anymore.
You could also sketch, like already said, with a verry light H pencil. but DON'T press had on the pencil, or you will see it when you color the drawing.