You can follow the general setup guide at https://crowdcontrol.live/setup for extra help with the Twitch Extension, the Crowd Control Desktop Client and other options.
Crowd Control support is built into the game! All you need to do is press START in the Crowd Control desktop app after you launch the game!
After that, you should see “Connected” in the top left corner of the game.
If you are not seeing “Connected” after pressing START in the desktop app, you can press the “9” key in game to force a reconnect.