On your computer, go to Gmail. Enter your Google Account email or phone number and password. If information is already filled in and you have to sign in to a different account, click Use another account. If you get a page that describes Gmail instead of the sign-in page, at the top right of the page, click Sign in.

Go to http://accounts.google.com/signin/usernamerecovery and enter any email accounts or phone numbers that you've had for a while and which may have been used as recovery info. The “find your email” page can help you locate any forgotten Google accounts.

You can access the Account Recovery form from the password-assistance page by selecting "I don't know my password," entering your username, and clicking the link to verify your identity on the following page.