Protect your score

Your credit score has a major impact on the interest rate and other terms of your credit cards. Know how your actions affect that score.

You'll need a minimum FICO credit score of 730 to qualify for the best cards. Because 15 percent of your credit history is based on the longevity of your credit accounts, try not to close your oldest card unless necessary. If you don't like a card's interest rate, use it sparingly to keep it active; many issuers are now closing cards because of inactivity. But pay it off in full each month.

Don't do anything rash, such as cut up all of your cards or suddenly take out five new ones in hopes of boosting your available credit. Both approaches could backfire. Having a mix of credit lines, including credit cards, is important to your score, but opening too many new cards will shorten the length of your total credit history and make it look like you need lots of new credit, a danger sign.