When you are hitting balls at the driving range, pace yourself. Don't hit a hundred balls in 10 minutes--take your time. When you get tired, go hit some putts or call it a night. By rushing yourself, you?re practicing a swing you?ll never take to the course. Instead, go through your pre-shot routine and use the same rhythm that you?d use on your course. A basketball player practicing foul shots doesn?t shoot a dozen shots in 30 seconds; he goes through the same routine he?ll use in a game. If you keep practicing after you?re tired, you run the risk of getting sloppy and allowing a swing flaw to creep into your game. Worse yet, you?ll wake up sore the next day or develop an overuse injury.