Write an article based on this "Back up your device. Determine your model and operating system. Prepare your device. Download jailbreaking software on your computer."
Jailbreaking can create problems, so it's a good idea to back up your device before attempting to jailbreak it. To do this:  Connect the iPod to your computer. Launch iTunes. Select your iPod. Under Manually Back Up and Restore, select Back Up Now. The jailbreak process will vary slightly with different software, and you may need to know your specific model and the operating system it's running. On your iPod, select Settings > General > About. Under Version, it will tell you what firmware you're running and the model in brackets.  An iPod Touch 2G will likely be operating iOS 4.2.1 or 4.1, but it's possible that it may be running something from iOS 3. The model should either be MC or MB. Have your device ready by keeping it on, locked, and not connected to your computer. Some of the most popular programs for jailbreaking an iPod Touch 2G are limera1n (Limerain), Redsn0w (Redsnow), and GreenPois0n (GreenPoison), which can be downloaded from Guide My Jailbreak.  Note that Redsn0w is compatible with iOS 4.2.1 and the MB model of the iPod Touch 2G only. If you are running a different iOS or have the MC model, you will have to use different software.  Make sure you download the appropriate version depending on whether you're using Mac or PC.