Though each branch of the military differs in their guidelines for Tuition Assistance, they all have a few things in common. If you are in the Army, Navy, or Marines you need to seek command approval for tuition assistance. You need to do this on a class by class basis in the Marines and Army. With the Army, you can apply through their website. In addition to needing approval in the Navy, you must have an education plan agreement prior to starting classes. In the Air Force, you can apply for tuition assistance through the official Air Force website, and even earn a 2 year degree through the Air Force’s community college. For the Coast Guard, you must apply in advance of starting classes.
For specific information about each branch of service, please refer to those articles.