Perhaps your family has fallen on tough times. But it's never too late to start repairing your credit.

The single most important way to improve your credit score, experts say, is to pay all bills on time. Late payments typically are reported to the credit bureau after they're late by at least 30 days.

On the other hand, don't assume because you've had a late payment that your credit is ruined for life. The late payment record generally is removed from your credit report after 36 months, notes Edie Milligan Driskill, financial planner and author of "Repairing Your Credit."

There are several things you can do to improve your credit history.

First, understand that lenders often use a credit score to measure your credit risk, and to determine your interest rate and other credit terms. However, there is more than one credit score, and each scorer may have a different rating scale.

The FICO score, offered by Fair Isaac Corp. is most widely used and typically ranges from 300 to 850. It is based on information contained in your credit reports. However, many lenders, while considering FICO scores, factor their own scores based on their own criteria.

Even Fair Isaac has more than one type of credit score. One, for example, is tailored to those who have not yet built credit, and may consider nontraditional factors such as rent receipts. In addition, each major credit bureau may provide a different FICO score, based on information from its own credit report.

You're entitled to one free copy of your credit report annually from each of the main credit bureaus at www.annualcreditreport.com or by calling 1-877-322-8228. Credit scores, though, are tougher to get. If they're free, they often either are not FICO scores, or they're a limited-time come-on to sign up for a costly credit monitoring service.

Your credit report includes your name, address, Social Security number, birth date and employment information; your credit accounts -- including the date you opened the account, the credit limit or loan amount and the account balance and payment history.

It also has a list of everyone who accessed your credit report within the last two years. Plus, it has public record information from state and county courts, information on overdue debt from collection agencies and bankruptcies, foreclosures, suits, wage attachments, liens and judgments.

Want to look good to a lender? Your employment history and residential history are important. Change your employer numerous times without increasing your wages or moving a lot could imply instability.

Refrain from closing existing credit card accounts, Ms. Milligan Driskill suggests. Lenders look at the ratio of available credit to the amount of outstanding balances.

Keep plenty of cash on hand and consider using cash as collateral to secure credit cards.

Ms. Milligan Driskill also recommends putting higher down payments on cars and homes. "Use your cash [savings] to stabilize your credit picture and financial security."

Stay clear of finance companies. Banks, she says, often look negatively on finance company lending because you are considered at risk for not paying your bills.

Also, avoid churning credit cards! Opening one account to get a discount on the price of an item, while closing another is considered a bad sign. So is conducting numerous balance transfers.

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