Logon using your admin logon. 

After a successful logon you will be taken to the admin home page. 

Click + Add a subscriber.

Choose the category of subscriber: Billing, Trial, Internal, and Example

Billing is for new subscribers that have signed a contract. 

Trial is for potential subscribers that want to try before they buy. 

Internal is for subscriptions that are for your use.

Example is for subscriptions that you create that will be replicated to be used as a starting point for other, new subscribers. 

After choosing the category of subscriber, name the Subscriber, choose an example subscription to copy from Copy example, the Brand, set the File limit according to the contract (if a Trial, Internal, Example, subscription leave the default of 2 GB), and the Default time zone. When finished entering the options, click  OK and the new subscription will be created.