Some may think this sounds funny, but I would get a job. Something unrelated to medicine. Wait tables, tend bar, caddy, anything that gets you out of the hospital and working with real people. It shows you are a well rounded person, and that you didn't get through life and school without ever having to work for it.
It would also help to start getting to know some of the important faculty in the department you are interested in. You can set up shadowing opportunities during the summer of your MS1 year, and of any interesting cases come up, offer to write one up for a case report.
Just my opinion!