As a freshman in college I started thinking about what would be important things to remember about having a roommate when I got there. This is what I came up with:
1. You are sharing space
Make sure you are allowing each other equal space and that you don't take away from each other, be respectful of what each other has.
2. You will probably have many differences
If you find yourself disagreeing with your roommate don't make it a big deal, after all you live with each other and don't want to make things tense between the two of you. Respect each other's opinions and beliefs even if they are the complete opposite of your own.
3. Always be open minded
Keeping an open mind while having a roommate is very important. It will keep you from making snap judgements and allow you to get to know each other on a personal level.
4. Always talk to each other before you make a decision
When it comes to the dorm, that is where both of you live. Before you invite people over or change something about the room, ask to make sure it will be okay with your roomie. You don't want to cause unnecessary tension.
5. Sometimes you will have issues
If you have a problem with your roommate, let them know in a nice way. Talk to them about, after all it was probably just a misunderstanding that can be reconciled in a matter of minutes.