Step 1) Go to your Facebook business page.
Step 2) Then click settings in the top-right.
Step 3) On the left-menu click on 'Page Roles'.
Step 4) Under 'Assign a New Page Role' enter in firstname.lastname@example.org.
Step 5) Click the box on the right and click on 'Admin' then click the 'Add' button.
Step 6) Facebook will ask you to put in your password again for security reasons. That should be it.