Well, you can get the FAFSA done and out of the way as soon as possible.. like when you do your taxes, or now if you can project that.
Most of the private loans people advise you to wait until you have your award letter from the schools and all yoru fafsa stuff done before you apply for private loans, since their loan amount is dictated by FAFSA, esentially. I would do the FAFSA now or as soon as you can and then just sit on that until you know where you will be going and how much more you will need above FAFSA. There really isn't anything else you CAN do as far as private law loans go. Having the FAFSA done ahead of time will help though so once you get your acceptances, the process will be quick.