When Conference Room Mode is enabled on the Apple TV, you will have the option to enter a custom message. You may also set a custom background image when this option is enabled, so that you see instructions for connecting with AirPlay over your own image instead of the standard Apple TV screensaver. This will display the SSID of the wifi network that the Apple TV is connected to as well as the name of your Apple TV.
You can find this option in the Apple TV Settings menu, under AirPlay.
For use with Ditto, you will need to ensure that the computer is connected to the same wifi network identified by the Apple TV. Visit https://account.goditto.com/connect and enter the Room Code associated with your Apple TV to connect and share. More details on connecting with Ditto can be found here.