All of this is good advice. I seem to be doing the opposite of the freshman 15, though, because I forget to eat when I am stressed, so I lost 8 pounds first semester (gained a few wrinkles, though, so it evens out). I also sacrificed sleep, social outlets, fun, and relaxation, and I nearly had a nervous breakdown. Second semester, I actually had a more stressful personal life, but I allowed myself to get sleep, to relax, to put some fun into my life, and my grades actually went up, not down. I gained back 5 of those lost pounds, too.
One thing I'd really like to stress, particularly to those of you who are coming straight out of undergrad, which you entered straight out of high school:
Your grades are important, but one test, one grade, one class, does NOT define you. You may be one of those lucky ones who manages to avoid personal trials and tribulations, but most of you WILL, at some point, stumble. You might even outright fail a test. At the very least, you will find you are now amongst a whole bunch of people who are used to being the best of the best, and you will not always do as well as you think you should or even as well as you know you could.
And it's ok! Do not allow yourself to be defined by one, or two, or sometimes three crappy performances. Dust yourself off, move on, and do better the next time.
Our Associate Dean took pains to say to all of us during orientation that he wanted us to get used to the idea that, yes, we CAN sometimes do poorly. And he didn't want to have anyone go home after failing a test and call their parents to come and get them, because we will all falter at times. It does not mean you cannot do it. It does not mean you are a failure.
Shoot, at some point, many of us will make a mistake that might even cost an animal its life. So failing a test--not such a big thing.
So expect it. And then figure out how to do better. But do not allow yourself to be defined by every test.