Step 1: Download the latest version of iTunes (10.5) for Windows or Mac.
Step 2: Back your iDevice up through iTunes. We’re not expecting anything to go majorly wrong – it’s just a precautionary measure.
Step 3: Update your device to iOS 5.0.1.
Step 4: Download the latest version of Redsn0w for Windows or Mac.
Step 5: Run Redsn0w. Select “Extras”, followed by “Select IPSW”, and point it to the iOS 5.0 firmware file, Select the appropriate firmware file tailored for your iDevice.

Step 6: Then hit “Jailbreak”, and select “Install Cydia”. Follow the steps through DFU mode, and then Redsn0w will apply the jailbreak.

Step 7: Once everything is complete, you will need to boot tethered. Launch Redsn0w, select “Extras”, followed by “Just Boot”. You will need to perform this action every time your device is switched off or rebooted.