Justuno designed Sub Accounts to help those clients who have more than one website and would like to activate Justuno on all of them. The major benefit of using sub-accounts is that you have one login for all accounts, making it drastically easier to manage multiple Justuno accounts. Here is an article about embedding Justuno on multiple sites (if you're not interested in sub accounts). The main reason users want to use a harder method like embedding Justuno on different sites instead of using Sub Accounts is that the billing will be on one account. Here is how billing works for sub accounts.
1. Head to your settings panel on the left-hand side of your dashboard below the Justuno logo. Hover over My Account, then click Add Sub Account.
3. Enter in your new accounts information. If you're an agency representing a client, you have options to use their email address for the login and who receives which notification emails; there is also the option to use the master accounts billing information.
4. How to revert back to your "master account". Hover over Admin, then click Revert to Master