Instructions
Visit Bungie.net, and create an account using the Microsoft Windows Live ID system. Ensure that your Gamertag has been linked to your Live ID profile by checking the preferences on the official Xbox website.
Sign into Bungie.net using the Live ID and make a Bungie identity and profile. The Bungie profile is separate from your Live ID, and will be used to contain all of your play data from "Halo Reach," "Halo 3" and "Halo 3: ODST."
Start "Halo Reach" on your Xbox 360 while signed into Xbox Live with the Gamertag registered to the Bungie and Live ID accounts. Go to the "Armory" option and customize your Spartan's armor, gender, colors and voice. Save your preferences, and exit the Armory.
Log into Bungie.net and click on "My Profile." Click on the "Halo Reach" button listed under your Gamertag to see the newest version of your Spartan character on Bungie.net. Clicking on the character opens a new window containing a large rendered image of your Spartan.