After Creating a Mailbox Template, you can then apply the settings to a single mailbox or group of mailboxes on the Apply mailbox templates screen.

You must first select the template you want to apply and then add the users you want to apply it to.

ApplyMailboxTemplate

 

In the screenshot above, the template Test Template 2 will be assigned to the users in the list.

After clicking apply 365 Command will apply the settings contained in the template to the user mailboxes.  When complete, if there is an error, you can click on the red exclamation point to get more details on the settings that were not applied.