1. Download the mod files you want to install.
2. Extract the mod files to a USB drive.
3. Connect the USB drive to your Xbox 360.
4. Start the Sonic Generations demo.
5. Go to the Options menu.
6. Select the Game Data tab.
7. Select the Load button.
8. Select the mod file you want to install.
9. Select the Install button.
10. Wait for the mod to install.
11. Exit the Options menu.
12. Start a new game or load a saved game.
13. Enjoy your modded Sonic Generations demo!
Note: Some mods may require you to have a modded Xbox 360.