Yes there is a way to be guaranteed a flight slot going in. I am in a similar situation as you, I'm 23 & have a degree and have looked at the various opportunities offered by the different branches. Like I said above if you have any interest in flying helicopters check out the link to army woft above. They had something like a 67% selection rate last year for civilians, since they don't require a degree you should have a leg up especially with civilian flight time on top of your degree. Basically you put together a package, go before a board, and if selected off to flight school.
If you are interested in the airforce you might need a gpa waiver, I don't know much about that but if you did good on the afoqt I assume you could get one. The way it works for civilians is you can apply to what is called a rated board, there are two a year. You can apply for pilot, cso, uav pilot, and air battle manager. You can apply for one or all and list your preferences. If your selected you go to officer training school, then pilot training or cso training, ect. BTW the last rated board had like a 69% selection rate (
http://www.rs.af.mil/recruiteronline...p?id=123291224). Now is actually not a bad time to apply. See a recruiter and tell them you want to apply. Also, your young so you could always enlist in the air force if there's a job you like and then apply to become an officer in a few years once you build up some experience.