Pay a higher payment than the minimum and you will pay it off faster. If you pay it more often then you can also avoid some of the compounding interest. For example if you pay $300 at the middle of the month and $300 at the end of the month, you save two weeks of interest that would've applied to the first $300, than if you simply paid $600 at the end of the month.
While you have to pay the required minimum, you can also add additional funds and have them applied against the principal. The advantage there is you can do it when you have the extra funds available and are not obligated to do it every month. Another good route is to refinance and go from a 30 year to a 15 year loan. With the lower interest rates, you might find your monthly payment doesn't go up all that much and your home will be paid off in half the time.