My biggest recommendation when you are asked to fill out information about yourself so your school can connect you with a potential roommate (or mentor or study group) is to be honest about who you are. Don't answer based on who you want to be or how you hope to act, but think about what your life is like. If you're messy, admit that. If you like to study with lots of noise in the background, confess. If you love video games, say that. If you love to read, but think that accounting is going to make you more money, think about your future. You are much more likely to have a good experience in education if you are honest about who you are.
This applies to numerous other aspects of school as well. If you join a morning study group because you want to be a morning person, but you have trouble getting to the session, that does no one any good. If you sign up for the once-a-week class because getting it done seems like a good idea, but you know you can't pay attention for 3 hours straight, then look at a different class. If you have a group project and volunteer to do the first part, but know that you have to work that weekend and you won't make the deadline, either don't sign up for that part or be honest with your group about your time pressures.
Like you've always heard, honesty really is the best policy--and this applies when talking to your professors as well. If you messed up, admit it. If you need help, ask for it. If you don't understand, raise your hand; don't assume you will magically understand the concepts later...Be honest now and the rewards will pay off with a more successful academic career.
Becky Anderson graduated (some number of years ago...more than two hands worth) from Dartmouth College with a degree in English, and then went on to Trinity College to get a Master's in American Studies. She currently resides in Maine (where her roommate / husband is also messy, but he was honest about that from the beginning) and has worked at Macmillan Learning, in two separate stints, for about ten years.