You can install the latest tvOS 9.2 beta without losing your settings and applications using the Apple Configurator 2 for Mac utility. However, this will still require a computer and a USB-C cable. Fortunately, a new way to install the tvOS beta on Apple TV has become known without using a computer at all, you can do it instead iPhone.
As before, you will need a developer account and a tvOS beta configuration profile. In addition, you will need iPhone with the DropBox and Remote applications installed. Of course, you can enter all the necessary web addresses manually, but with Remote everything is much easier.
Step 1: Download the Configuration Profile from the developer portal. Save the profile to a folder on DropBox so you can access it from iPhone.
Step 2: On Apple TV open Settings> General> Privacy and check the Send data to Apple checkbox.
Step 3: Now press the Play button on Siri Remote.
Step 4: Click Add Profile> OK.
Step 5: In the window that opens, completely remove the URL from the text box.
Step 6: Launch DropBox on your iPhone and open the folder with the profile you downloaded in step 1.
Step 7: Click on the down arrow located next to the profile. Select Send Link, then Copy Link.
Step 8: Launch Remote Control on iPhone and connect to Apple TV.
Step 9: Click on the Keyboard button and paste the URL you copied in step 7.
Step 10: At the end of the URL, replace 0 with 1 and hit Return.
Step 11: As a result, the profile will be added. After that, you will be prompted to restart Apple TV. Click on Restart Now.
Step 12: After rebooting, go to Settings> General> Software Updates and check for updates. The tvOS 9.2 beta should be available for download.