Three things off the top of your head?
1. Defending; I panic when I lose control of the ball and end up trying to slide tackle or lunge my way to success.
2. 1 on 1's. Often through on goal and I'll try to be clever and turn back on the chasing defender. Fail (although when this works, it's so satisfying).
3. Giving the ball away from goalkicks or trying to tiki taki my way out of trouble in my own box.