Once your student is approved, and ready to post, you will naturally need a place for them to stay on campus, or off it. Younger students in the 17-20 range should probably pick a room in the dorms, though that's not a hard and fast rule. Married students, or students 21 or older may have a flat off campus, though you'll want to make sure that your student's background indicates they have enough money to support themselves in the city.
Dorm Life: Getting into the dorms is easy. Every undergraduate student at the University is guaranteed housing in the dorms, regardless of financial aid. The choice is then to live in Proudstar Hall or Sydney Hall. Sydney is a more traditional dorm, with two to a room and a large community. Proudstar hall has a suite-system for rooms that encourages smaller, more tight-knit groups of students.
If there is room in a room already occupied by a student, you can generally move your student into the room, though it's always a good idea to contact the player of that student first. If there are no free spaces, or you simply fancy your student being a bit more separated, you can feel free to create a new room to stay in.
Transfers between rooms are not a problem, it is assumed that the students complete all the paperwork necessary for moving in with a friend without actually having to play out the process.
Off Campus Life: Should your student be financially solvent enough to afford a London flat, then you should come up with a concept for a living space that meets your student's financial means and describe it in the Off Campus Housing forum. That will give your character's friends a place to go when they're looking for him or her.
If you have any questions about the housing situation, or how to set things up, feel free to ask the moderation staff.