Sleep enough. Eat well. Don't forget the fitness. You can't let the body go, he's essential to mind.

I'd recommend some sort of mind training... just relaxing doing what other people says is relaxing almost never helps (beach, book, etc).

Check this out [english audio]: http://www.youtube.com/watch?v=vHjyMq6eZB8

This one is good too: http://www.youtube.com/watch?v=ogH3KAge6zw