Unless you really want to stress yourself out and have the time to do so, don't try to have too many majors/minor. Just stick with the basic medical school requirements. This way you can spread out your hardest classes.
If you are in a frat, don't live in the house for more than one year. No matter what day of the week it is, people will be partying and bugging you if you're trying to study.
If you DO live in, find a roommate who is generally more quiet and understands your schedule.
Take the MCAT earlier in college, rather than later. This way, in the case that you do well, you can have a relatively easy senior year and enjoy your last semesters of college.
Try to make friends that have your same major and classes. You can have people to study with if you need help or be your lab partners in class. They will also be the only ones who understand how stressed you are when you are studying for the MCAT.
Become best friends with the libraries on campus. Go there before, between, and after classes as much as you can so you don't have an overload of work at night.
Drink lots of coffee and energy drinks to keep you awake!