What is something you wish someone would have told you before heading off to college?
I wish my parents would have warned me about finances. Which includes student credit cards, etc. They taught me nor told me anything about finances, which unfortunately hurt me for quite a long time. I maxed out several credit cards and took me a long time to rebuild my credit for lower interest car payments, getting a house, etc.
So I would say besides the possible normal things: make friends, be careful at parties, take breaks for studying so you don't get burned out, etc. Make sure that you are stable with your finances and don't get caught up in trying to keep up with college friends, etc. Mom & Dad may be have more money than your parents and pay for that OR they may be getting themselves in financial holes. Especially if you have student loans that you'll have to pay for when you leave college.
Go to class. Plan to spend 2-3 hours studying for every hour of lecture. Attend your professor's office hours and any TA review sessions. If there is a test bank, use that as a study tool to understand what your professor wants you to focus on for the test.
I wish someone had told me that it's okay if it takes you a while to find friends you want to keep for the rest of your life and that your roommate doesn't have to become your best friend. Also get involved- whether it's a club that sparks your interest, residence hall government, sports, research, or student leadership related, many of your best college memories are going to come from activities outside the classroom. Also your RA really is there to help and they want to help. If you need something please go ask.
I wish someone told me how extremely important it is to plan everything and most of all, how to learn best.
An amazing book is 'how we learn' by Benedict Carey but you can look it up on youtube. I wish we had that option back then too. Of almost every book is a tedtalk or a youtube film. That will help you to get the content a lot faster. There is also this brain coach online: Jim Kwik. He has lots of podcasts on iTunes that are amazing to learn faster, read faster and remember everything better. www.kwikbrain.com