Tell them information that pertains to the account.
For example. The last thing you did on the account, and events to have previously occured while you were on the account. Maybe even include what things are in the bank. If your account has a bank pin, I would include that as well.
Provide as much additional information you include in the bottom part, because it is essential in unlocking your account at all times. It is used lastly just to verify that you are the "true" owner of the account.