Your email address is often the first thing a coach or recruiter sees from you, so it should make a good impression. Paying attention to "little things" like your email address brands you as a serious, conscientious young athlete.
Your email address should be Firstname.Lastname@gmail.com (or whatever email service you prefer). If that's not available, use your first and last names with your jersey (or another) number, such as JohnSmith10@gmail.com. Capitalizing the first letters of your first and last names will make it easier for college coaches to remember you.
Avoid cute, funny or confusing email addresses. If you are a point guard or a wide receiver, Butterfingers99@gmail.com will send you to the reject bin. If your email is UNCNumber1fan@gmail.com, the Duke University coach will scoff when you express interest in becoming a Blue Devil.