Jailbreaking your PlayStation 3 console involves overwriting the operating system and replacing it with custom firmware. Since the release of Sony's system update 3.55, jailbreaking attempts haven't been successful. If your PS3 console has a system update on it newer than 3.41, you first must downgrade your PS3's firmware before applying the jailbreak.
Downgrading Your PS3
Insert a USB storage device into your computer.
Download Lv2diag.self and PS3UPDAT.PUP and save them to your USB device. These files can be found on PlayStation 3 forums.
Remove the power supply from the PS3 console and insert the USB storage device into the USB port nearest the Blu-ray disc drive.
Plug the power supply back into the PS3 console. Press the "Power" button on the console quickly followed by the "Eject" button to launch the factory reset. Your PS3 will beep four times and turn itself off.
Turn the console on by pressing the "Power" button on the console to complete the downgrading process. Remove the USB device after the downgrade is installed and label it to differentiate it from the USB that you will use to jailbreak your PS3.
Jailbreaking Your PS3
Download the Jailbreak PS3 3.73 file launcher onto your USB drive. Extract the files by double-clicking the file launcher. Remove the USB drive after the jailbreaking software has been extracted.
Remove all games, Blu-ray discs and USB devices from the PS3 console.
Disconnect the PS3 from the power supply and insert the USB device into the right-most USB port. This is the port nearest to the Blu-ray disc drive.
Plug the power supply back into the PS3 console.
Flash the PS3 console by pressing the "Power" button quickly followed by the "Eject" button.
Turn on your PS3 controller and select "OK" when asked if you want to perform a system update.
Restart your console to complete the jailbreaking process.
Jailbreaking software is neither sponsored nor endorsed by Sony. Jailbreaking your PlayStation 3 may result in irreversible damage to your console and will void your warranty. Access to the PlayStation Network will be revoked on your jailbroken PS3 along with any associated user accounts.