Make sure you go to class. 75% of doing well is just making it to class, which amazingly gets harder the less classtime you have.
Also, don't settle. When you go to college you immediately have very easy opportunities/temptations within arms reach that you don't have to work for at all - reach out beyond your zone a bit and find worthwhile people, activities, groups, etc. to get involved in.
Well, since I spent much of my college years doing what most of the posts in this thread are talking about and regretted it later, I will go the route LOMS did.
1) Take college seriously. You are there for a reason and that reason is to get a good education, degree and a much better job after getting out than you would have when you entered. The way I did most of my college, I did not work towards that goal at all.
2) That doesn't mean you can't have fun. Just realize the work comes before the fun. Again, have fun. You will still look back and think this was one of the funnest parts of your life. Just make sure you take the rest seriously.
3) Get involved with people and organizations that help you, not hurt you. Don't hang out with too many people like me. Find the people in your major of interest that take it seriously. Have fun with them and motivate each other to do well.
I know...I sound like a 48 year old dad. Well...I am that. I just learned some things after looking back at my time there compared to other people's time there and theirs was much more beneficial to them long term.
You can absolutely get a GREAT education at UNL. You can also slide through getting nothing out of it. Make sure you are on the right side of that statement.