Also, something I did know before college (thanks to friends that went a year before I did) is how easy it is to blow a scholarship and not return for your sophomore year. If you have to keep a certain GPA to renew your scholarship each year, do whatever you can to keep it. It’s a lot easier to loosen the reigns and let your hair down later than it is to buckle down after everything has gotten away from you.
What was the best advice you got while you were in college? Try out for theatre productions. Seriously. Made great friends, had a ball, and most importantly, learned confidence and tremendous public speaking ability.
Most useful classes which I still use to this day: Business Communications and Western Civilization.
Go to whatever resume workshops, career planning events, internship fairs, and summer missions work booths you can, and it’s never too early.
What do you wish you had done differently in college? Not much. I stayed out a year before going, and that was good. Learned humility and job discipline. I spent five years there, and that was good, as I experienced all sides of academic and campus life. Spent two years in the dorms, two years in campus apartments, one year off-campus—definitely recommended to experience all types of living. The only regret I have is signing up for a credit card in my final year. Don’t do it! It’s a trap!
But if you go to a college because it's "prestigious" and choose a major because "it's what I need to get into ... (job, grad school, etc.)" and you slog your way through four-plus years of "survival" and end up with a two-point-something GPA, get ready for the next TEN years of your post-college life to be just like the last four. Not that I speak from experience, but you get my point.
Do everything you can to set yourself up to succeed. And build on those successes. There'll be enough failures along the way in ANY college experience to teach you some "hard knocks" lessons.