Adding An Admin Role To Your Facebook Page

You'll need to be an admin to manage roles for your Page. Learn how to see what your role is.

There's no limit to the number of people who can have a role on a Page. Learn more about what each Page role can do.

Give Someone a Role

If you're an admin:

1.    Click Settings at the top of your Page.

2.    Click Page Roles in the left column.

3.    Type a name or email in the box:

o   If the person is your Facebook friend, begin typing their name and select them from the list that appears.
o   If the person isn't your Facebook friend, type the email address associated with their Facebook account.

4.    Click Editor  to select a role from the dropdown menu.

5.    Click Save and enter your password to confirm.

Source: https://www.facebook.com/help/187316341316631