1. On your phone, go to Developer options -> Wireless debugging. 2. Tap 'Pair device with QR code' and scan the QR code shown here. 3. Ensure your PC and phone are on the same Wi-Fi network.
Status messages will appear below. If pairing fails, try toggling Wireless Debugging off and on, then try again. After successful connection, close this dialog and use the main 'Start Stream' button.