References are good and bad. Imo.
If you want to improve, using a heavy reference and copying it exactly to learn details of, say, a person's face is fine. I prefer to call it "cloning" but it's great for practice. *shrug*
Some artists clone a picture but make variations on color or add odd things to it. Which is lovely, but I'm not experienced in... artful art? ^^; Expressive art? Eh, Iono.
It does take skill even to clone, though. My teacher says it's good for "training your eye." I like unique pictures better, but you gotta start somewhere. Long as you learn something by doing do. Or as long as it's fun. :P
Cloning fanart is bad, though. Not that people do it around here, but it ticks me off on deviantART. :P So~ don't~ do it~ without permission and credit~