How to lower stress before big tournament

How do you calm yourself or focus before a tournament? I get very stressed and it affects my playing. Wondering if there is a way to approach the game calmly and not freak out/think about consequences/not worry about the competition involved. Basically, to just not worry at all and just focus on the game. What are some ways of doing this?

1. Not caring about your rating is the ideal, not looking at your rating (for months or years) is what works in practice.

2. Read "The Inner Game of Tennis," by Gallwey.

3. Forget about your rating.

4. Play in the moment. Don't think about wins or losses, just good moves.

5. Forget about your rating.

6. Meditate 5 minutes each morning.

7. Lose, lose, and lose again, until the horror of loss is drained from your system.

8. Forget about your rating.

9. Read all the interviews ever given by the fearless Hikaru Nakamura. He is the man without fear.

10. Forget about your rating.

Eat something that makes you take a big dump. After that, nothing will bother you and you'll be glad you got that episode over with.

Some people like listening to Jazz and Blues music for a few hours others do Tai Chi or Yoga before playing in a tournament and some people like swimming for a few hours in the morning before they play.