If you will need financial assistance to attend law school, you must pay just as much attention to the financial aid application process as you do to applying to law schools. Most law school catalogs explain how the financial assistance application process works. It's a time-consuming exercise, so make you sure you plan for it, and be aware of the deadlines for each law school (they vary). The Official Guide to ABA-Approved U.S. Law Schools lists those deadlines, but I suggest that you confirm them by checking individual school catalogs.
It may also help to contact an organization called "Law Access" which, to quote from their materials, is "legal education's largest private nonprofit financial aid services program." Through Law Access, you can put together a total financial aid package combining federal (low interest, delayed repayment) and private loans. To reach the Law Access program, you may call their toll-free number, 800-282-1550.
While you are in college, it's essential to maintain a good credit record. If your credit is poor (and it's surprising how little it takes to earn a poor credit rating), you may encounter serious difficulty when trying to borrow for law school. With that in mind, make sure to pay credit card, utility (including cable) and rent bills on time. If you are in risk of falling behind in those payments, don't ignore them; instead, contact the creditor and discuss what to do next. If you take time off between college and law school, and undergraduate loans become due, be extremely careful to make your payments on time.