How to find your Gamer ID
To find your Gamer ID have another player (or your captain) click on your name while in the HD lobby and click the Report Player option. From there they can screenshot the ID to download from the headset or have them send via Facebook Messenger.
If you have a Mac/iPhone you can copy text from an image in the preview/photo app respectively. For those of you on windows you will need to transcribe your ID.