Follow these steps to add an agent to your Customer Center:
Hit Customers on the left hand side of your page
Hit the Add Agent Button
Enter all of the Agent's Information
When done hit Add Agent

If you would like to add multiple customers at once, you can do do by importing a list of customers to Aryeo.
Hit the Import button in the Customer Center and download the template. Once that is filled out you are able to import multiple of customers to Aryeo at once.