First, find out who the good teachers are. Ask your adviser; poll older students; search the Internet; and consult the teacher-evaluation guides available at most colleges.
Pay close attention to what others are saying and writing and then summarize their arguments and assumptions in a recognizable way. Work especially on summarizing the views that go most against your own.
Do ask questions if you don’t understand the professor’s point. Do not, however, ask any of the following: “Will this be on the test?” “Does grammar count?” “Do we have to read the whole chapter?” “Can I turn in my paper late?”
I would add:
Each semester, pick one class you worry might be too hard for you, and one that’s easy but engaging.
Never choose a class just because your friend(s) will be taking it. Each course is a chance to expand your social circle.
Schedule yourself a block of library time for reading/studying, just like it’s a class.
If you can’t find courses that interest you, take a semester off and re-evaluate.
What would your college advice be?