I haven't done it in a while (since I was in high school), but I think I should start copying people's pieces. I thought it would be good for practice. I sometimes can't think of what I want to draw. Copying the piece I like would help with dealing with this problem. Of course when I copy a piece there are some stipulations, like no tracing, and giving links and information about the piece and artist I copied. Most of the reason I want to copy is to learn different ways to draw and I also have to learn proportions better.
"Good artists copy, great artists steal." - Pablo Picasso