Shoot Pool, not people
Any negative emotions you exhibit will only serve to empower your opponent. Don't ever forget that! My favorite money player years ago was "Little Al" Romero. He never showed any emotion at any time during a match, either positive or negative. If he missed a shot, he didn't shake his head or make a face. He just sat back down with a completely straight face as if nothing had happened, not saying a word. I never forgot that. He was the only player who was that calm all the time. And he was a Winner!I just set my expectations low and understand that the preferred result isn't always going to be the actual result.
Pressure is (mostly) created by the self, not by others.
I don't dwell about missing a shot or shape, it happens.
And, imo, once you learn how to accept ALL results in a logical manner, you will be able to reach your greatest potential.
Albin Ouschan is a prime example of this.
He learned to control his emotions and now plays at a consistently high level. He doesn't always win, but his emotional control gives him the greatest opportunity to succeed.