The biggest piece of advice I'd probably give out is that you'll need to be ready to take a lot more initiative for learning any concepts you don't immediately understand from a lecture. High schools (at least, in my experience) do a lot more to make sure that students understand every point of every lecture, usually by assigning lots of homework for every day. College doesn't do that so much; so if you're not confident in your understanding of something, it's on you to find problems of your own to solve and/or seek out classmates who can explain it.
Yeah I was told that at my orientation. They pretty much said that if you don't understand something try to talk to your professor sometime after class to learn it and also you'll hopefully build a better relationship with them.
Thanks for your advice.