Protect Yourself. Avoid using your debit card to make online purchases. It might be inconvenient, but it sure beats having your money stolen. Also avoid using your debit card to pay bar and restaurant checks because the server physically takes your card away to complete the transaction.nline, they might try phishing you via email, posing as your bank or another reputable agency and requesting your card information and PIN number. Always contact your bank directly -- not by replying to a possibly phony email -- to verify such communications.