Things You'll Need
Instructions
Update your PlayStation 3 system software. You will need to have version 2.40 or later. Select "Update" under the settings option in your XrossMediaBar to update your system software.
Update the PS3 game of your choosing. Some earlier PS3 games added trophy support after their retail release and will need to be patched. The update will happen automatically upon running a game that has an available update while your PS3 is connected to the Internet. Not all games have trophy support.
Play the game of your choice. You will need to complete specific objectives to earn specific trophies. For example, the "Bullet Counter" trophy in Killzone 2 requires you to reload your firearm manually 100 times. When you reach the conditions for a specific trophy, a notification will appear in the upper-right corner of the screen.