A good way to get a head start is by paying off the interest on the loan while you're still in college. (financialwellness.org)
While the minimum payment is required to go towards paying off interest first, you can direct any additional payment you make to be applied towards the principal first. (creditsesame.com)
While it's common to think of it that way - pay off the interest first, then the principal - that's not actually how your payments work over time. (money.stackexchange.com)