Talk with a recruiter, study for and take the ASVAB, you want a good score. The better the score the more job opportunities you will have. From there, select your job, recommend not going “open” unless you are sure you will be okay with whatever job you get put into.
Do your research! Then you will sent to basic training, then technical training and finally your first assignment.
I applied in-person. The process took 3 months. I interviewed at US Air Force in Feb 2012
Interview
You go and talk to the guy, then you go to meps, take the ASVAB, then you dicuss jobs with a counselor, then you sign for a job when it opens with your recruiter. You prepare for bootcamp and leave on your date.