I would like to highlight four "fundamentals" in badminton which I think are very important, especially for young players. A good understanding of these fundamentals and performing them correctly will go a long way to achieving maximum capabilities.
These four very important fundamentals are the grip, footwork, stamina and the service.
Now that you have graduated from backyard badminton, you can no longer rely on physical ability alone to win games. It is time to develop tactics and strategies a game plan to out-think and beat your opponent. By identifying and focusing on his or her weaknesses, you are beginning to use your mental acumen to win. If you play without thinking you will lose without realizing why you lost.