If you're a male U.S. citizen, aged 18 through 25, and are living INSIDE the United States or its territories, or if you have an APO/FPO address, you can register with Selective Service on line.
If you're a male U.S. citizen, age 18 through 25, and are living OUTSIDE the United States, you can register with Selective Service.
EARLY SUBMISSION OF INFORMATION: If you are a man who is at least 17 years and 3 months old, you may complete this form to submit your registration information. The information will be held on file and processed automatically when you are within 30 days of your 18th birthday, at which time you will receive a confirmation.
It is important to know that, even though someone is registered, he will not automatically be inducted into the military. In a crisis requiring a draft, men would be called in sequence determined by random lottery number and year of birth. The same law also requires all male U.S. citizens, age 18-25, who are already registered for the draft to report any change of address within ten days.
You may report your change of address online.
For full information about the U.S. Selective Service System.