Inviting users to your domain will send them domain invitations so they can be able to join your domain.  Below are the steps on how to invite a user to your domain:
Domain administrator invites a user
  1. In My Domains page, find the domain you just created and click Manage Domain.
  1. You will be directed to the Manage Domain page. This page allows you to invite other users to join your domain. 
  1. In the Domain Users section, click Invite users to your domain. There are two ways you can search users:
  1. Select Alias or Name and enter the corresponding User Alias/Name of the user you want to invite to your domain.
  1. Click Search.
  1. Click Invite this user. You will receive a confirmation message stating that the user has been invited. 
  1. The user invited has to sign in and accept the invitation to be an official member of your domain. See the next steps for instructions to your domain users on how to accept the invitation.
NOTE: A message informing the user about the invitation will be displayed in the user’s home page so he/she can immediately see when logged in. 
Domain user accepts the invitation to join the domain
  1. While logged in as the domain user who is invited, click on My Domains.
  1. Find the domain under the section I have been invited to the following domains and click on Join to accept the invitation.