Instructions
Download Games
Turn off the Xbox 360. Attach the hard drive to the hard drive bay on the left side of the Xbox. Turn the Xbox on and select the "My Xbox" tab on the main menu. Select "Game Marketplace."
Find the game you want to download. You can browse by title, genre, popularity and newly added games. Select the game you want to download.
Select "Confirm Download." Select "Hard Drive" as the storage device. If it's a demo or a free game, the download will begin. If it requires Microsoft Points (virtual money purchased using real money), the amount of Microsoft Points it costs and the amount of points you have in your account will be displayed on screen. If you don't have enough points, you'll be prompted to add some using a credit card or prepaid card.
Enter the requested credit card information or prepaid code, select the amount of Microsoft Points you want and confirm the purchase. After you confirm, the download will begin.
Remove Games
Select the "My Xbox" tab on the main menu.
Select "System Settings," then "Memory."
Select "Hard Drive." Select "Games" or "Demos" (whichever fits the content you want to delete). Select the game you want to delete. Select "Delete" and select "Yes" when asked to confirm the deletion.