Through the match stix. You rank the hospitals for each rotation 1-35 in the order you are most interested. Then the computer program does it's best to give everyone their top choices. It doesn't mean you get your #1 choice, you might very well. We are told that the worst you will get is your #5 choice. And that most people get 1, 2 or 3.
A regional campus model was started this year. This is where you spend the whole year at a cluster of hospitals in NJ, or 1 hospital in Brooklyn, or 1 on long island, get the idea? It is for people who want to stay in the same place for the whole year. You apply and interview so that the DME can be sure that they like you. They don't want to be stuck with someone for an entire year who they feel is not compatible. If you don't get the regional campus (I didn't), you do the matchstix with everyone else. No big deal.
There was actually a really big interest in the regional campus this year, and that is why lots who wanted it did not get it. There were only 16 spots for the NJ regional campus, and 41 applicants. However, there are an addittional 12-15 spots with in the NJ hospitals left for the matchstix. So, I may very well end up in the NJ hospitals anyway, since I ranked them as #1 for each rotation.