As with any crime, you can't guarantee that you will never be a victim of identity theft, but you can minimize your risk. By managing your personal information widely, cautiously and with an awareness of the issue, you can help guard against identity theft.

Don't give out personal information on the phone, through the mail or over the Internet unless you've initiated the contact or are sure you know who you're dealing with. Identity thieves may pose as representatives of banks, Internet service providers and even government agencies to get you to reveal your Social Security number, mother's maiden name, account numbers, and other identifying information. Before you share any personal information, confirm that you are dealing with a legitimate organization. You can check the organization's Web site as many companies post scam alerts when their name is used improperly, or you can call customer service using the number listed on your account statement or in the telephone book.
Don't carry your Social Security card; leave it in a secure place.
Secure personal information in your home, especially if you have roommates, employ outside help or are having service work done in your home.
Guard your mail and trash from theft:

Deposit outgoing mail in post office collection boxes or at your local post office, rather than in an unsecured mailbox. Promptly remove mail from your mailbox. If you're planning to be away from home and can't pick up your mail, call the U.S. Postal Service at (800) 275-8777 to request a vacation hold. The Postal Service will hold your mail at your local post office until you can pick it up or are home to receive it.
To thwart an identity thief who may pick through your trash or recycling bins to capture your personal information, tear or shred your charge receipts, copies of credit applications, insurance forms, physician statements, checks and bank statements, expired charge cards that you're discarding, and credit offers you get in the mail. If you do not use the pre-screened credit card offers you receive in the mail, you can opt out by calling (888) 5-OPTOUT. Please note that you will be asked for your Social Security number in order for the credit bureaus to identify your file so that they can remove you from their lists and you still may receive some credit offers because some companies use different lists from the credit bureaus' lists.
Carry only the identification information and the number of credit and debit cards that you'll actually need.
Place passwords on your credit card, bank and phone accounts. Avoid using easily available information like your mother's maiden name, your birth date, the last four digits of your Social Security number or your phone number, or a series of consecutive numbers. When opening new accounts, you may find that many businesses still have a line on their applications for your mother's maiden name. Use a password instead.
Ask about information security procedures in your workplace or at businesses, doctor's offices or other institutions that collect personally identifying information from you. Find out who has access to your personal information and verify that it is handled securely. Ask about the disposal procedures for those records as well. Find out if your information will be shared with anyone else. If so, ask if you can keep your information confidential.
Give your Social Security number only when absolutely necessary. Ask to use other types of identifiers when possible. If your state uses your Social Security number as your driver's license number, ask to substitute another number. Do the same if your health insurance company uses your Social Security number as your account number.
Pay attention to your billing cycles. Follow up with creditors if your bills don't arrive on time. A missing bill could mean an identity thief has taken over your account and changed your billing address to cover his tracks.
Be wary of promotional scams. Identity thieves may use phony offers to get you to give them your personal information.
Keep your purse or wallet in a safe place at work as well as any copies you may keep of administrative forms that contain your sensitive personal information.
Cancel all unused credit accounts.
When ordering new checks, pick them up at the bank, rather than having them sent to your home mailbox.

Source: Federal Trade Commission