Instructions
Download the Iron Man skin.
Download the IMG Tool.
Install the IMG Tool by double-clicking on the downloaded icon.
Launch the IMG Tool by double-clicking on the installed file.
Click on the "Edit" button. Locate and click on the Iron Man skin which you downloaded and press Enter.
Quit out of the IMG Tool application.
Launch the "Grand Theft Auto: San Andreas" game by double-clicking on its icon. When you begin playing, your character will look like Iron Man.