umm...this may sound lame and all, but the way I deal with stress is to solve my rubik's cube. It annoys everyone around me, so I can't do it during a game, but it really gets the edge off. It also isn't very helpful to you unless you want to take the time to learn to solve
Chess Stress

I to have problems with stress. I am not as involved as you are in Tournaments, although I would like to be. I understand the stress you are talking about though. That stress has lost several games for me in the end game or even before. Knowing that I could win, have a great position and get so excited I can not even see the move I should make.
I end up having to pause and take a deep breath, to relax myself and slow down. Reminding myself I have plenty of time and to use the time wisely. This does seem to help with the anxiety of a stressful situation. This is my favorite way to deal with stress. It is simple and it works. I hope maybe it will be of help to you.

never would have guessed greenhornet. i am not 21 so nicotine does not work. I do meditate though thx for thought
anyone else?

Punch a kitten.
Na, just mucking about. Create an alter-ego. Make him good at all the things your not - have you seen or read fight club? Do that - without the fighting :)

Hi i am fischeryouth. To undrestand this thread you first must know a little about me. I am a younger club player and in real life am around a 1600 player (i am much better in real life than on chess.com) I have beaten much higher rated people (1900s-2200s) but not in tournaments. It seems that in tournament play i can not sem to calm down enough in the last round to win it all. I have only won one tournament but have lost to weaker opponents in the final rounds of tournaments because of my inability to deal with stress! SO PLZ WHAT IS YOUR FAVORITE WAY TO DEAL WITH STRESS????
p.s I have found that a mantra is pretty effective
I have found the more negatively I am thinking the better I play.

Playing under pressure makes you thinks better, thinks deeper. Read my profile and you'll understand what I means. In every game, always presume that your opponent would makes the best move. That's how I learned to handle over anxiety.

thx those who replied and just as a note today i was in a tourney and did some of the things from this thread and PLAYED THE BEST GAME OF MY LIFE no joke!
Hi i am fischeryouth. To undrestand this thread you first must know a little about me. I am a younger club player and in real life am around a 1600 player (i am much better in real life than on chess.com) I have beaten much higher rated people (1900s-2200s) but not in tournaments. It seems that in tournament play i can not sem to calm down enough in the last round to win it all. I have only won one tournament but have lost to weaker opponents in the final rounds of tournaments because of my inability to deal with stress! SO PLZ WHAT IS YOUR FAVORITE WAY TO DEAL WITH STRESS????
p.s I have found that a mantra is pretty effective