Reserve the type of dorm room that meets your privacy needs. Although dorms with single rooms are rare, many colleges have quads, which have two bedrooms that accommodate two students each and a living space that all four share. Though you must still share space in a quad, the extra room makes it easier to have a private conversation or study.
Create a privacy schedule with your roommate. Carve out blocks of time in which each of you can use the room privately. Post the schedule, and agree to discuss any changes or requests for additional privacy, such as if you have to study for an important exam or have a date. Evaluate and revise the schedule regularly to reflect changes in each person's class and work schedules.
Buy or make a room divider. Folding screen dividers can be stored behind a door or under a bed when not in use, saving space in a small dorm room. You can make a divider by hanging a piece of nylon string from the ceiling and mounting a curtain, or simply using thumbtacks to hang fabric between the two sides of the room.