As promised, here is the follow up tutorial for performing an untethered jailbreak on iOS 5.1.1 using the traditional DFU method. This tutorial is for the latest version of RedSn0w 0.9.12b1, and only works with A4 devices and below (A5 devices are not compatible with this method). If you want to use your A5 device — iPad 2, the new iPad, or the iPhone 4S — then see our previous Non-DFU mode tutorial for RedSn0w.
In most cases you should use the Non-DFU method for jailbreaking your devices, even if it's an A4 device. The exception comes if you have a lot of media stored on your A4 device or below. If you have a lot of media on your device, the iPhone Dev Team advises that this traditional method for jailbreaking may be a best practice due to iCloud syncing issues.
Take a look inside for the full walkthrough...