I contacted mine about a month before school started. First I introduced myself and a little bit of my background such as family and hobbies and such. Told her what major I'm going for (obviously). And then mentioned some big things for the dorm room that I had. I also mentioned other ways to get a hold of me as well.
And then I waited for her response. I actually did it through snail mail because that's about all the school provided me; name, address, and major.
I also ended up going through 2 roommates before I even moved into my room.
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