If I were to talk to myself as a high school senior I would say flat out, "Make sure you choose the school for your liking, and give your self options." As a senior I focused only on a few schools and it was for basketball, I kept a narrow mind. So if I were able to talk to myself I would lay out more options for schools to see what else was out there. I would tell myself to not just base my decision on the school with the best basketball team or the one who seems to be the better teammates. Yes it's a big choice to play a sport at a higher level and you want to be with people you'll get along with but look at more school rather than just three or four. " Get yourself out there, dive in and find what works for you!"
Going back to talk to myself as a highschool senior, knowing what I know now, my strongest piece of adivce is to be ready ahead of time. Do not procrastinate, do what needs to be done in transitioning to college. Always stay positive and make sure to keep your head above the water, not getting too stressed out or you will only drive yourself lower than you'd actually like to be. Keep yourself organized and have more than one plan incase the first does not fall through.
If I could go back in time and talk to myself as a high school senior, I would tell myself to attend a community college first and then transfer to a 4 year school. That is the one thing I regret. I think I was just overwhelmed with being on my own and didn't really focus too much on school. Now that im at Middlesex I feel more focused and comfortable with earning my degree successfully.
I found that college is a lot more work than high school. You really need to crack down, study and do your homework or you will fail. It's going to be tough, switching from doing almost no work outside of school hours to doing just as much work at home as you do in class, but taking the time to make sure you understand everything will be worth it in the end.
Make sure you check out all of your college options. Make sure you ask a lot of questions when you are choosing your classes. Look into and apply for every scholarship that is available.