I get nervous or scared if I focus too much on the outcome of an upcoming event. Hope for a good outcome causes nervousness, and dread of a bad ending causes fear. In turn, these feelings hurt my performance under pressure and make bad outcomes more likely.
I find the best way for me to approach important events is to pay attention to how I conduct myself rather than the outcome. I can't control all the variables of fate, but I can control my actions. Focusing on what I can control gives me peace, confidence, and strength. And regardless of results, I can be proud if I conduct myself well.
So I make note of qualities I admire in people and I try to embody those features myself: Be polite but firm. Stand up for your interests. Speak slowly and look people in the eye. Never reach the end of a hard workout and regret that you could have gone harder. It's okay if your body gives out, but your will should not. Be forthright. Address the elephant in the room. Start conversations with interesting strangers - don't pass by opportunity for lack of guts. If you make eye contact with someone, smile and say "hi". Ask for what you want. Accept failure graciously knowing that experience leads to excellence. Take pride in your work. Tell the people you admire how you feel. Be slow to judge people, but act on your judgements. Don't hide your beliefs - be an ambassador of undervalued wisdom. Look for opportunities to do something good for others. Be truthful, even and especially when it hurts. Keep an optimistic attitude. Feel painful or joyful emotions deeply, but don't linger over them for too long. When it's time for fun, have fun! And when it is time for work, do work.
I am a very flawed individual and often fail to embody these traits. For example, I severely lack boldness. But keeping them in mind gives me something to strive for.
In poker, the right question to judge your performance is not "did I win?" but "did I make the right calls?". There is too much chance in the game for even the best player to win every time. But if you play well, you will end up ahead in the long run. Life is the same way.