Login to the Admin Panel
Every domain has a default admin account. The email id of this account will be postmaster@<your domain>. The credentials for this account will be sent to you via email on the registered email id for your organization. Use these credentials to login to the Admin Panel for your domain.
To provision users in a domain, you can use one of the two options:
Provision Alias ids
Alias ids have to be associated with an existing user account. The alias ids for users can be set using the Admin Panel.
Provision Groups or Distribution lists
Groups or distribution list have email ids associated with them and have one or more members. When a mail is sent to a group email id, it is automatically delivered to all the members of the group.
You can provision group ids and their members using the Admin Panel.