To add additional accounts to a device:
Select Settings from the navigation bar at the bottom.
Select Experimental features, then select Multiple Accounts and Library Sharing.
Turning on this feature will add an Accounts option in the Settings sidebar.
Select Accounts from the Settings sidebar, then select Add Account.
Follow the on-screen instructions to set up a device unlock code, then hand the headset to the other person to add their account to your headset. They will be guided through the initial setup including logging into Facebook, adjusting headset fit, and setting up Guardian.
Note: When you turn on this feature in your experimental settings, you can still log in to multiple devices at the same time. However, you will then be prevented from using the same account to run the same app across multiple devices simultaneously.