Try to arrive a few minutes early to classes and talk to people and be social with classmates. Joke around. Show them that you're fun to talk to and possibly hang out with. If you have a test of project, you could ask fellow students if they would want to come over and study or meet somewhere and then you might end up going out for a drink or soemthing after. I went to a school in a city where I didn't know a single person so I really had to take the initiative to introduce myself to as many people as I could and let me tell you, it definitely paid off. Don't be scared to put yourself out there.