Adding managers allows you to share control of your page posting and settings with multiple people without having to share your personal login information. Managers have all of the capabilities of an owner, except for particularly sensitive capabilities such as deleting the account or managing access.
How To Add Managers To Google+ Page
==> Log in to plus.google.com
==> Access your page management options by selecting "Pages" from the Google+ main navigation. After clicking on "Pages", you will see a card for each of your pages.
==> Click Manage this page to open the information the page that you'd like to manage.
==> Once you are on the page you want to manage, click on "Dashboard" from the Page main menu, then scroll down till you see the "View all Managers" link. Click on it.
==> Click on the "Add Managers" button
==> Enter the email address of the person you want to add as manager or invite by profile
==> Click Invite.
The invitee will be notified of a pending invitation to become a manager. When a manager invitation is accepted, the owner of the page will be notified via email.
The owner and all managers can view the names listed on the Managers page.
How To Remove Managers from Google+ Page
==> To remove a manager, or remove yourself as a manager of a Google+ page, click on the "view all managers" link on your page via "Dashboard" menu item as explained earlier. Then, click the X associated with the person you'd like to remove.
When a manager is removed, both the former manager and the page owner will be notified and told who removed them.
NB: When you remove a manager, they’ll no longer be able to act as that page, or take any kind of administrative actions. However, all of that manager’s past posts, comments, and other actions will remain intact.
I hope this helps.