My best advice is be as prepared as possible going in; have your supplies, housing, etc in order. Maybe even prepare some throw in the oven meals ahead of time. That way, if it gets crazy, you aren't wasting time running to the store for groceries, laundry detergent, highlighters, etc.
After that my suggestion is to try to keep up or even stay ahead. At some point, you will likely have something come up that will put you behind. If you were barely on top of things, that can be devastating...if you were a bit ahead, you have some buffer. Remember, things happen; cars break down, apartments flood, flu spreads, and family memebers have emergencies. You may need that little bit of space just to manage.
Accept that you are not going to get it all right all the time. You will miss things, you will forget things, you will have brain lapses, and you will want to rip your hair out. It's ok. Try to stay healthy; a week down with illness can be crippling. Stay flexible; you may have to completly change your study tactics depending on the class and the professor. Get help before you are in serious trouble. IE if you walk out of an exam saying 'I failed' talk to your advisor and student services immediately; don't wait till the exam comes back..that could be a week or even two down the road, and you will have even more to recover from.
The thing that helped me (and is still helping me) is trying to relate what I did each day back to the big picture. I have copies of NAVLE study books, and sometimes I just would drag one down (like anatomy) and flip through it till I found a few questions that I knew the answers to, to give the details some personal relevance, or when learning tendons I would call up a vet friend and say 'at what point will I use this in practice?'
While there will be times you need to be selfish and use your time and energy for you, don't forget friends, family, community. They will keep you sane.