I took my test May 22nd. Having done pretty well, I would advise you to do a few things:
1. Start getting information on the MCAT now. Learn about the test, the subjects covered and the structure.
2. Do well in your chemistry biology and physics classes. This will form a foundation for your MCAT prep and prepare you for the information covered.
3. Set a date 3-4 months before your MCAT, make some time and start studying then. I can say from personal experience that any more time and I would have been burnt out.
4. Take as many practice tests as possible in a fashion similar to what you'll be seeing on test day. Do the whole test in its entirety (no cheating 😀) in stressful situations as well as at your home (i.e. library).
I used the Kaplan course and really enjoyed their materials, but any comprehensive course or set of books should work. Its just important that you put the time in, practice the tests, and don't get burnt out!
On a side note, I thought audio osmosis was a lot of fun, and would suggest it for walking around to classes, when driving, etc.
Good luck! You can do it!