1.) Realize that NS is way harder than high school. I was the kind of student who did really well in high school w/o usually studying very hard...NS is generally the opposite. Don't let readings and test materials pile up, try to overcome (or at least tame) procrastination tendencies, and set aside SPECIFIC blocks of study time.
2.) Along the same lines, try and find one or two people to study with-too many more, and it won't be productive. Also attempt to find study partners whose learning styles/paces/habits work with yours (do they learn through listening, writing, etc.? are they learning at roughly the same pace as you?)
3.) If you make mistakes, don't endlessly beat yourself up. If you're honestly trying and NS really is for you, a few bumps in the road will be not be the end of your NS career. As someone who is about to be a junior, I look back and realize that wailing and gnashing of teeth over one bombed anatomy test (I didn't realize until much to late that I didn't know those origins and insertions of muscles as well as I thought...) and other similar disasters was a lot of wasted energy over something that didn't even dent my semester grade much.
4.) Don't whine ENDLESSLY about NS. Newsflash: we all know that the tests are hard, clinical is too early, your clinical instructor is a monster and that nursing research class puts you to sleep . I know from personal experience that it's really tempting to whine and throw yourself a giant pity party, but doing it all the time just leaves you feeling even more stressed and wiped out than ever.
5.) Of course you want to avoid any "toxic" people in your nursing classes, but try to find a couple of close nursing school buddies. My two closest college friends are nursing students. Honestly, I don't know what we'd do with each other. We're always cheering each other up and keeping each other's stress levels down...and really, who else will gladly hear your stories about the DISGUSTING greenish-yellowish sputum your patient spewed all over your face?
6.) As people have already said, SLEEP and EXERCISE. Sometimes these things will be the only calming influences in your life. If you're really having problems sleeping, for crying out loud go to a counselor or doctor! This sounds extreme but I have seen waaayyy too many nursing students about to go off the deep end b/c they just weren't sleeping.
7.) Give yourself some alone time to do some completely mindless, fun stuff. The occasional Saturday afternoon spent lying in bed and watching chick flicks while stuffing your face with junk food will help restore your sanity :-)
And I'll stop now that I've written a book! :chuckle