From the Studio of your event, go to the "Event data" section, and then "Sessions".
Once in the Sessions tab, click on the session you want to make private. Once you are on the session, go to the tab entitled "Preferences".
Here is where you can choose to activate the "Make the session private" option. When the option is activated, the session is visible only to those registered with it. The option is active when the button is colored and turned to the right (see below).
You can alternatively choose between two ways of activating privacy options for Sessions:
1. You can hide the Session completely and pre-add all the attendees you want for it. You need to enable the option Make this session private and disable the option Allow everyone to register for this session. After that, you must go to the Attendee’s tab for the Session and click +Add One Person or +Add several at once, then copy/paste the email addresses of all of the Attendees you want to register for the session. Finally, only the selected Attendees will be able to see this Session on their Agendas, however, participants still have the option to unregister for the Session.
2. Within the desired Session Preferences, you can choose privacy off, but you can create and choose one Group of People who can only be registered for the Session in order to keep it restricted. Please go to Event Settings < Groups < Add a Group and then create a new category in order to add exclusive members to be part of private Sessions. Anyone could see this Session on the Agenda section but only authorized people that belong to that group can register and watch it.
Besides making the sessions private individually, you can also make all the sessions private at once by clicking on Sessions Settings> Default Session Preferences and toggling right on the “Make the session Private" option.
Note: Once you add participants to a private session, they will have access and they will have it on their agendas (My Event) by default.