I also endorse the "don't skip class" mindset. Also, if you don't get something for one of your classes, don't be afraid to visit the professor or TA during their office hours. They'll be more than happy to help you, assuming you've already at least put in the effort to read over the topic in your text book once or twice. (I'm a TA, I know. And if you bug a TA for a simple question you could have answered by opening a book, you're probably going to be put on the s*** list.)
Don't pee in the woods while tailgating. You will get a ticket.
Tailgate. Then actually go to football games.
If you want good grades (and you're not a genius) think of your school work like a full time job. If you're not putting in 40 hrs/week, you're not doing what you need to. Any time beyond that 40 hours is free for the taking - intramurals, partying, etc.
Workout as often as you can. I've never been in as good of shape as I was in high school. Not putting as much effort into working out in college caused more than just a "freshman 15", that I still haven't gotten rid of.
If you get a bike, get the ugliest, nastiest, most functional bike you can find. You want it to work. You don't want it to get stolen. Every penny you invest in a bike U-lock is money well spent. Anything <$40 will result in a stolen bike.
Lastly, TV is a huge time suck. Pick 2 or 3 shows that you can't miss and watch them. Time spent watching any other TV is time you could spend either having fun, or getting better grades.