Go to usmc.com and fill-out the information request, and within a week the Marine Corps will contact you. After they speak with you and see what you would like to do, they arrange for you to take your ASVAB if you had not taken one already or your score was not high enough for the job that you asked for. After your results come back you are give your job options, after you choice one, you will take a PFT, and then get checked out by medical. if you pass all of those steps then the only thing left is to sign your name to a contract for a set number of years.