In order to use the Live Stream option you will need a YouTube account (Twitch is no longer supported). Once your account is set up, you will need to enable live streaming through your YouTube account settings.
  1. Select  Multiplayer
  2. Select League Play
  3. Select a series in the League Play menu and find the Live Stream option.
  4. Activate your Call of Duty Live Stream the next time you enter the Live Stream menu. The game will generate a unique web address.  
  5. Input the unique web address in your computer's browser to view your game.
Note: You will need to be connected via HDMI with a minimum resolution of 480p. There are a maximum number of live streams. If your Live Stream doesn’t go up at first, take a breather and try back in a few minutes. Also note that Live Streaming only works in League Play modes, both solo and team games. So before your league game starts, make sure to turn on the Live Stream option so you can broadcast your games around the world.