If you can't remember your password, or can't sign in, start by resetting your password using these steps:
  1. Click the "Sign In" button, then click the "Forgot Password" link.
  2. Enter the email address you used to create your profile.
  3. Within a minute or two, you'll get an email with a password reset link. Click that link, and you'll be prompted to create a new password.

If you don't get the email in your inbox, check your spam/junk folder too. If you still don't see it, 

If you created a profile using "password" as your password, the first time you click the verification link in the email, you will be automatically signed in. However, you won't be able to sign in again when you return in the future. You'll get a message about having a bad password. To fix this, simply follow the numbered steps above to reset your password.