I've been concentrating on keeping my thoughts positive lately. I recently read an interview with an athlete who makes it a point to try and focus on only positive things. If something negative creeps into his mind, he follows it up immediately with a positive thought. I thought this was a pretty good idea, and I've been trying to follow it.
At first I felt a little silly but I figured I'd "fake it 'til I make it" and I think it's working. The more positive I am, the better I feel. And the easier the whole thing is.