The more I read about and understand odds and variance, the less I'm likely to tilt. The two plus two forums have helped me immensely in this regard.

I think the best thing you can do to avoid tilt is to mentally prepare yourself BEFORE sitting down to play. Every serious player should have a checklist handy. How's my attitude? Am I tired? Impatient? Grouchy?

I think it pays off to have a brief mental conversation with yourself. I tend to reenforce in my own mind how important it is to play with both discipline and fearlessness. Having a mantra can also help. Usually I tell myself that I will play to the best of my ability regardless of results, that I will focus on every hand and, win or lose, learn something from the session.

Once you do find yourself on tilt, I think the best thing you can do is take a 15 minute break. Sometimes taking a brief walk can help. This time can be used to make an honest assessment of whether or not you are capable of returning to the game and playing your A game.

Of course, I only play as a hobby and at small buy-ins. I'm sure it's a lot harder to stay on track when the mortage payment is on the line.