Budget, Budget, Budget!
This one I learned the hard way. The money would inevitably run out, and when it did, mom and dad weren't there to pick up my tab at dinner or put gas in my car. I learned the importance of looking at my monthly finances (which, let's be real, I was a poor college student, so it wasn't a lot). I calculated and kept track of how much I needed for bills and necessities and how much I could spend on the fun stuff.