In my senior year of college right now and these are the tips I have which might have been mentioned by others:
-Keep your dorm door open because people might like to pop in and say hello
-Be friendly and introduce yourself as much as you can. Everyone is knew and everyone is nervous because they've left everything behind. Try meeting new people and find those that match your personality.
-Don't talk behind other peoples back. If you don't have anything nice to say don't say it at all (most especially in a small college)
-Try to keep track of the calories and quality of foods you eat. The freshman 15 is a reality for a lot of people and can be more of a freshman 30 recently. Be active.
-Join clubs you find interesting. You'll find others like you and meet tons of new people.
-Invest on something cheap to put on your door knob if you want to prevent your roomie from seeing you in an interesting situation

-Take simple 101 courses your first year not only to get them out of the way, but because they're easy and give you time to socialize and learn about the college.
-Be courteous when you're hanging at someone's place you don't know.
-Play any drinking games by the house rules and don't complain
-If you're of the drinking type, get good at beer pong
-Enjoy. College is one of the greatest experiences in your life. It'll have its downer moments but it's been tons of fun.