1) Take care of yourself. During those last months of serious labbing I still took the time to exercise. Go for a long walk, take a run. Go for a swim. Anything that gets you moving. Eat right. Take care of yourself! It really helps you to get the most out of a 12 hour lab session.
2) Go for that first attempt even if you feel you're not ready. I've written about that before so go read that post as well.
Did you come here from Google looking for tech advice? I have a few of those as well but none of those made an impact as huge as the two above.