As a Business Mail administrator, you can create, edit, and delete email addresses and assign administrative privileges to other email users, which you'll manage from the Email Control Panel. Here's how:
Sign in to your Business Email account at http://mail.yourdomain.com (be sure to replace "yourdomain.com" with the domain name associated with your account).
If you're using the new Mail interface:
Click "Options" in the upper-right corner of the page, then choose "Mail Options" from the pull-down menu.

On the left side of the page, select the "Administration" option.

On the Administration page, click "Manage Email Addresses."

The Email Control Panel will open in a new window, where you can add email users, create aliases, and more.