Another way to build up your credit is to piggyback on someone else's credit card account. Ask a family member or your spouse to add you as an authorized user on that person's credit card. An authorized user is not responsible for the balance but benefits from the cardholder's payment history on that account. So make sure you choose a financially sound credit ride. A side note: Experian includes authorized user accounts only if the payment history is good, says Griffin.

Ulzheimer also suggests checking with your bank or credit union to see if overdraft protection on your checking account is reported to the credit bureaus. Sometimes, it is considered an unused installment loan on your credit report.

"It's not a bad way to get a good thing on your credit report," says Ulzheimer, "as long as you don't have to use it."

Stay on top of your new credit

Lenders love to see recent good payment behavior, so pay your bills on time and keep balances low. Aim to pay off credit card balances every month to keep debt from snowballing out of control.

Check your credit report to see which items are weighing on your score, says Trey Loughran, the president of personal information solutions at credit bureau Equifax. For specific clues on how to fix your credit, order your credit score with your report -- it will provide key reasons why your score isn't higher.

If you're a carrot-and-stick person, consider a credit-monitoring service to keep you motivated, says Griffin.

"It's important to check your credit score periodically, especially when you're in the recovery phase," Paperno says. "And it might be better than you think."

How long will it take to recover?

Unfortunately, knowing how to fix your credit is only half the battle. The time it takes to rebuild your credit depends on the catastrophic event and where you started. Generally, borrowers with lower credit scores experience a smaller drop in their scores after a huge credit event compared with those with great credit, according to studies by VantageScore and the Federal Reserve.

If you get a mortgage modification after being delinquent on your home loan, it could take as little as nine months to lift a credit score of 625 to above 700 if all debts are brought current, VantageScore found.

The effects of foreclosure linger longer. Your credit score will start to rebound in as little as two years if you keep all other accounts in good standing, according to myFICO. However, the Fed study found that a third of prime borrowers never saw their credit scores return to pre-delinquency levels, even 10 years after the foreclosure.

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The road back from bankruptcy is longest. The VantageScore study shows that raising your credit score is difficult until the public record comes off your credit report, either seven years for a Chapter 13 bankruptcy or 10 years for a Chapter 7 bankruptcy.

That doesn't sound good, but all is not lost.

"The severe impact from a bankruptcy occurs in the first two years and will roll off from there," Davies says. "If you consistently pay on time, in two to three years, you will get into a reasonable score range."

This article was reported by Janna Herron for Bankrate.com.