First, I would tell myself that I need to make sure that I do well my senior year because I won't get financial aid unless I have good grades. Second, despite me getting really homesick, it's still a good idea to go to a college away from home because it's a good experience. You get used to being away after a while because you make new friends and you adapt well to the college. Also, you need to make time for everything because your assigned a lot of work. Especially if you're taking a 5 unit class. The last thing I would tell myself would be to have fun with it, you will hit a bump on the road every once in a while, but just hold on and you'll survive college.
The first thing I would tell myself is to not rush into things and enjoy your time taking the classes and transitioning. It's a great opportunity to experiment with different fields, which could ultimately lead to discovering your career interests. But at the same time you should keep making appointments with your advisor to make sure you're on track to transferring/graduation. Also, each semester keep a to do list handy because those deadlines can come and go faster than you would ever imagine. I really wish I would have been more organized when it came to school related things outside of my classes (such as graduation deadlines.)
I would let myself know that college is a great journey and not to be afraid. Take advantage of all the education you can get while you are young. School is so much easy to get through if you do not have alot of distraction such as children. Starting college after high school is the best option and don't give up when things get a little rough.
Devout yourself now to working hard. College can provide a lot of fun and exciting new expirences, but it can also provide you so much knowledge and wisdom. Yes, play, have fun, but take advantage of all the oppurtunites to learn and prepare. They will serve you will and are just as exiciting.