Things You'll Need
Instructions
Go to the PlayStation Network site and sign in with your PlayStation Network login and password. Click "PS3 Demos" and select a game demo from the list of available titles. Click "Download" to save the game to your computer. These demos can be over 100 MB, so they can take a long time to download.
Insert a USB flash drive into your computer and open the icon on your desktop.
Copy the downloaded game demo to the root directory of the USB drive. Eject and remove the drive.
Connect the USB drive to the USB port of your PlayStation 3, located on the left side of the console's front face. Turn on the console.
Navigate to the "Game" tab of the menu. Highlight your USB drive and press "Triangle." Choose "Show Items."
Select your game demo. Choose "Copy" to install the game on your PlayStation 3's internal storage.
Press "O" twice to return to the "Game" menu. Scroll down the list of available games until you reach your newly installed game. Launch the game with the "X" button.