Instructions
Turn on the Xbox 360 and sign in using the offline Xbox 360 profile you wish to promote.
Navigate to the "My Xbox" channel. Select your profile tile by navigating to it and pressing the "A" button on the controller.
Select the "Join Xbox Live" option and when prompted to exit the session select "Yes." This will take you to the "Welcome to Xbox LIVE" screen.
Select the "Sign me up" option. You will be prompted to enter your Windows Live ID and password. When you have correctly entered the information, select "Sign In."
Enter your date of birth and location into the appropriate fields. Ensure accuracy, as this information cannot be edited once the gamertag is created.
Read the Xbox Live Terms of Use and Privacy Policy Statement. Click "Accept" to agree to the terms.
Choose whether you wish to subscribe to a Free membership or a Gold membership. Free memberships will be given a one month free trial of Xbox Live Gold.
Enter payment information if required for a Gold membership. Completely enter all remaining personal information such as phone number, contact information and Gamer Zone. You will be asked to confirm your membership and taken to a screen to create your gamertag. By default, the offline Xbox 360 profile ID will be appear in the gamertag field. Confirm that this is the gamertag you want. As long as that gamertag is available, the offline ID will be promoted to an online Xbox Live gamertag.