What do you wish you had known when starting college?

[Katy]

Some of my friends are nervous prefrosh and asked me to make a list of all the things I wish I had known when going to college so I made a list for them. It has stuff like "bring flipflops to wear in the bathrooms," "don't put styrofoam in the microwave," "bring a ton of quarters for laundry," and "this is how you cash a check."

Sadly however I am worried that I am going to not think of an awful lot of things.

So if you can think of something that you had to learn the hard way, or you had problems with, or just wish you had known before the problem was sitting right in front of you please post it here so I can be sure my list is as complete as reasonably possible.