Permission
A few weeks before my first set of finals when I was a 1L, an alum from my law school who graduated with highest honors gave me some great advice.
He said, "You have to give yourself permission, no matter how stressed you are, to do things for yourself. You have to sacrifice some things, but you can study for hours and still have plenty of time every day for the things that matter the most to you. You can exercise every day, spend time with your family and friends, read for pleasure, watch TV, whatever you want -- just not every single one of those things every day.
"Most important," he said, "you have to SLEEP. A full night's sleep is a lot more valuable than the study time you'd gain by giving up sleep."
It was true then, it's true now, and it will be true five days before the bar. :)