I would second what Chris said. Keep your grades up all the time, but especially in your first quarter/semester. It will do good things for you, and set you off on the right path. It shouldn't actaully be too hard to get all A's and B's for your first term. Just put your mind to it.
If you encounter any sort of competitions in one of your classes, make sure you try your very best to win.
As far as clubs and things like that, don't feel like you have to join right away. Focus on school, and if you are doing okay with that and still have time, then join something.
Last, you will encounter more sales pitches than you ever have in your life before. Be weary of any fliers for jobs like "summer work opportunity" or "$1000 per week" or anything like that. Be prepared because lots of people will try to stop you and try to sell you something, or hand you something, or tell you about something, or ask for money. Be very careful with who you talk to and who you give your information to. I'm not saying every path leads down a bad road, I'm just saying be careful.
Don't go out and get a bunch of credit cards or anything like that either. Trust me there will be losts of companies just jumping to give you one.
So, with all that said, good luck! And don't eat pizza
everyday. Visit Subway or something once in a while too. Have fun at college!
