Honestly the best advice I could give you would be to play hard every play and practice. Dont walk to the huddle or sideline, run, hustle is what coaches look for in players. Keep a positive attitude at all times, even if your losing keep your moral and the players around you positive. Be the first one to practice and the last one to leave practice, coaches love to see someone who is ready and trying to play and or improve their game. Dont be afraid to ask the coaches questions, they are there to teach you, if your not sure about a coverage ask them what would be the best way to play the reciever on the coverage. Most of all have fun, when you play the game and have fun playing it you will play better. Good luck with your pursuit ill be rooting for you.
"DAMMIT!!!!! I knew it, I knew it, I KNEW IT!!!!"-Immortal words of The Captain