Current 30-year mortgage rates

So, take some steps to raise your score. Pay down debt, especially on credit cards. Don't open new credit cards, but don't close old ones either. Doing that will reduce your available credit — which could hurt your score.

Get your hands on your credit reports and make sure there are no errors that could be dragging down your credit score.

A 2012 study from the Federal Trade Commission found that 20% of U.S. consumers had errors on their credit reports that needed correcting.

3. Consider a larger down payment

Homebuyers who can make larger down payments tend to land lower 30-year mortgage rates.

If you're willing to put more skin in the game, a lender will see you as a better risk and reward you with a better rate. As an added bonus, you won't be forced to buy private mortgage insurance, or PMI, if you can make a down payment of at least 20% of your home's purchase price.

Don't have that kind of down payment cash? If you're a first-time homebuyer, down payment assistance may be available in the form of a government grant or low-interest loan.

Private mortgage insurance is different from homeowners insurance, which you will definitely need.

More: How much should you put down on a house?

4. Pretend your loan has a shorter term

One smart interest-cutting strategy is to treat your 30-year home loan like a mortgage with a 15- or 20-year payback.

Use a loan calculator to see what your payment would be under a shorter-term scenario, then add the difference as a principal pay-down each month.