Learn a little at a time. Don't compare your knowledge to other's or to the total amount possible, just to what you knew before. Keep it up and you'll slowly get better and better over time.

I also find it useful to keep a short file of features I want to learn and features (1 or 2) I'm currently learning (trying to use as much as possible even if it slows me down a bit so that they'll stick in my mind).