Making good relations with people is key. If you see people from your lecture class go up to them, strike a conversation and get friendly with them. They are probably as nervous as you are regarding the whole experience of university etc. Another key reason is if you cannot make it to a university session, you could get somebody you know to collect important handouts from the lectures or even try to summarise what went on that day. Above all be friendly so you can interact with new people and make new friends, it never hurts to widen your friend circle and who knows they may even turn out to be some of the groups of people you stay in touch with for the rest of your life.