How to color this picture? Paint, water paint, colored pencils, oil pastels, exc?

So I sketched a picture and want to make it bigger. But I want to color it also. I am not sure what would look best paint, water paint, colored pencils, oil pastels, exc.? The picture is a hand stretched out with a dog tag chain wrapped around the fingers and the dog tags themselves in the center of the hand. On the wrist of the hand is carved "I LOVE YOU" and its bleeding. In the backround is the american flag wrinkled and a quote about love and war is written in Persian text at the top. What do you think? There will have to be shading because it is pretty detailed as to the wrinkles in the flag and the cracks/lines in the hand.