Put on the necessary NBA muscles, learn how to play in the big boy league, become a better teammate, and be willing to work to improve every aspect of your game. Obviously injuries and being in a bad situation can put a damper on things, but there is no substitute for hard work. First of all, hit the books. No university will come calling if you don't have the grades. Plus, you'll find something other than basketball that you really like (I found computers). Work on your conditioning. The NBA is full of athletes who have great endurance. You will want to run at least 2-3 miles every day and dedicate time to sprints as well. Also, walk up the steps to your school's football stadium. When I was in college basketball we ran at least 10 laps of stadium steps three times a week (one lap was up and down each hallway all the way around the stadium). Work on your strength: Proper weight training will help you withstand the abuse you will start playing basketball. If you play inside, it's a war of pushing and shoving to get the best possible position for yourself and to take away the best possible position for your opponent. I can't tell you how many times I've had bruises on my ribs, thighs, elbows in the face, neck, chest, etc. You need strength to endure these blows again and again