You have to have graduated med school to register, they confirm with your med school and receive a copy of your diploma. I wanted to take it earlier rather than later, but was not able to register until June or so, for an August date. My class was required to pass it during intern year, so we mainly took it in the fall. The rumors are true; 2 days and a number 2 pencil and you're fine, passing rate is like 98% and score is unimportant. Don't waste a vacation or anything studying, just show up and get it out of the way.