Knowing each person's rhythms can help you figure out what to expect day-to-day. Remember that both of you are probably living on your own for the first time and may be sharing a room for the first time. You may also learn that the habits you had in a family home differ from your habits in college. Give your roommate grace if they claim to be an early riser only to discover they have different habits in college. From there, discuss room volume and lighting for different times of day. These details may seem small, but they can begin discussions around which lamps, microwaves and other smaller items to bring that are not provided by the college.
When figuring out who will bring each item, talk through expectations for items in shared and private spaces. For example, just because one person owns the microwave should not mean they are the only person responsible for cleaning the microwave if you both use it. Although these conversations may not feel connected to decor, they will help set the tone for how you will decorate, together or individually.