How to Jailbreak an iPod Touch 3G or 4G
Usually I concentrate on writing about Cases, but here is a nice tutorial on how to jailbreak your iPod Touch.
1. Update your software. This is under the assumption that you've already updated your iPod Touch to iOS 5.1 (please note Settings—> General—> About—> Version should be 5.1)
2. Download the Redsn0w application. Download Redsn0w 0.9.10b6 for Windows from this link and Redsn0w 0.9.10b6b for Mac from this link and save the application in a folder named "Redsn0w" on your desktop.
3. Unzip Redsn0w. Double click the Redsn0w zip file and extract the application to the Redsn0w folder. Navigate back to the Redsn0w folder and launch the Redsn0w application.
4. Start the process. After starting Redsn0w, click on the Jailbreak button.
Windows 7 users should run the .exe in Windows XP compatibility mode (right-click on the Redsn0w .exe and select Properties, then select the Compatibility tab, then select Run this program in compatibility mode for Windows XP). Windows XP and Windows 7 users should run Redsn0w as Administrator (right-click on the Redsn0w .exe and select Run as an Administrator).
You will be prompted to connect your iPod touch to the computer and switch it off. Follow the instructions and click on "Next" to move to the next screen.
5. Put your iPod touch into the DFU mode. Redsn0w will walk you through the steps:
Hold the Power button on the iPod touch down for 3 seconds.
Now simultaneously hold the Home button and keep the two buttons pressed for 10 seconds:
Release the Power button while keeping the Home button pressed, until Redsn0w detects the device.
Your iPod touch should reboot now. Please remember to release the Home button. Redsn0w will now start preparing the jailbreak data.
6. Choose your options. You will be told to select the jailbreak options you want. Make sure Cydia is selected, then select Next to continue.
You iPod touch will be rebooted again and Redsn0w will now begin uploading the new RAM disk and kernel.
Once the jailbreaking process is complete, click the Finish button to exit the application.
7. Wait while your iPod Touch reboots. This can take up to 5 minutes. After it has done so, your iPod Touch should be jailbroken, and the Cydia jailbreak app on your home screen.
8. You will need to boot your iPod Touch tethered. Once Redsn0w is done jailbreaking your iPod touch, you will need to boot it tethered, which means that if you need to reboot your iPod touch it will be stuck on the Apple logo. You just need to rerun Redsn0w and this time click on Extras and then click on Just boot from the list of options and follow the on screen instructions to reboot your iPod touch.
Don't forget to always keep your iPod Touch protected.