Here are things I did after asking others the same question when I was in your shoes, so I wouldn't say, "i wish i did this."
If you've never taken any human anatomy course
before, I'd suggest that you just lightly review
basic anatomical terms like articulation, a nerve "coursing medially" as suppose to "piercing through this muscle", superior/inferior, abduct/adduct, inversion/eversion, sagittal, coronal, etc., since the professor may start using these terms without explaining them. But at the same time, you don't have to obsess over learning everything in Netter's before you start classes. If the notes are available over the web, maybe just download the first lecture or two so you have an idea of what will be discussed.
Just as long as you had a chance to preview the lecture/lab
material in Netter's before each class, you should be fine. I just finished an intense 7 week course of gross anatomy and I found it very helpful to photocopy the lecture notes and study them in with the cadaver next to you so you can visually see the origins and insertions, the course of vessels & nerves, etc. it also saves time since you're studying for both the practical & written at the same time....believe me, the bodies are usually A LOT different than what you see on Netter's or Rohen's atlas, esp. for the Head & Neck region.
Also, I love reading books on various non-medical subject matters, so before school starts...read up on whatever interests you (investment portfolios, politics, the arts, music, celebrity gossip, etc.)
Also, make sure you incorporate a regular routine of exercise before medical school so you'll make it a habit even during med school.....believe me even when you're tired, working out or cardio is MUCH BETTER at giving you energy than coffee.
good luck!
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Univ. of Minnesota Class of 2007
but a Physiology class would really have been helpful. Biochem here is taught from the perspective of a beginner, and taking Pysio would definitely have given me a more heads up on things 
