Take it easy. For starters, tensing up uses a lot of muscles, including the ones in the facial area—so being in a tense state gives you less control over your facial expressions! Don’t force anything, and as a favorite movie quote of mine goes, “Let the Force guide you.”
Talk normal. People can pick up information from the way you talk—your choice of words, the tone of your voice, etc. These elements change depending on your emotion. So talking “normal” and keeping your voice at a default level and being aware of this makes sure that your opponents don’t read you as much.
Look and act apathetic. Poker is an emotional, intense game with lots of highs and lows. You’ll have to be able to control the way you handle the game, keeping your feelings under the radar. Keep your face neutral. Role play that you’re the boss and the rest of the players are interns—this will help you psych them out into thinking that you’ve got more experience and better cards than they do.
Be a graceful winner. When it’s down to you and another player and the other person goes belly up on you, don’t gloat over the win. Smile, relish your victory, but don’t rub it in the face of the loser. At the same time, make it look like your win was totally expected and planned. That way you show that you are graceful in triumph while at the same time…
Know how to face defeat in style. As with any game, you can and will lose. The difference lies in how you take the loss. Smile as if it was all part of the plan or the grand equation—it’ll throw other players off your game.