Instructions
Use the free trial that comes when you first get you Xbox console. This option is perfect for gamers who have no yet signed up for Xbox Live. Turn on your Xbox or Xbox 360 and make sure that the ethernet cable is plugged into the back to provide Internet access.
Click on the "Join Xbox Live" option from the main startup menu.
Choose a unique username that will be shown when you play games online. Fill in the rest of your personal information until you get to membership options.
Choose the "Silver" option. Don't choose to redeem a 48-hour trial because choosing silver will get you a month free of service. Click on the "Confirm" button and you'll receive your one-month free trial. This method will only work if it's the first time you've signed up for Xbox Live services.
Buy online games that come with redeemable coupons for free months of Xbox Live. The more popular online multiplayer games typically come with these coupons. Just click on "Redeem" option after you click on "Join Xbox LIve." Enter the code number and you'll be able to continue playing online for free.