I am also trying to make varsity this year. When I made the Freshman team last year we had about 30 kids trying out and only half the kids made the team. I made sure that if i made a bad play or if I was upset with anything, to not show an emotion about it. You just have to collect yourself and get it next time. Make sure your using two hands when warming up and throwing or fielding (when someone throws the ball to you almost put your thumbs together). Make sure you do those type of little things. If there is something on the ground thats not supposed to be there, or if someone could trip on it, pick it up. If you miss a pitch, get right back into your stance and get ready for the next pitch. Remember, some coaches only spend a few minutes on a player and they are trying to select the top 15 or so out of the 30-50 kids that try out. When you pitch make sure you are consistent and hit your spots. Be smooth with your mechanics. Try your best and dont let your emotions get the best of you (even when you make a great play, dont make a big deal about it, just move on no matter how good you feel). I hope this helps.