jailbreak iOS 6 (with Cydia) for iPhone 4 and iPod touch 4G

The chains have been broken ... at least for iPhone 4 and iPod touch 4G owners (chains: Shutterstock)

The Northern Hemisphere autumn is usually a slow time for jailbreaking. Apple releases new iOS firmware, along with a shiny new iPhone – and both typically need time before they can be hacked. The members of the iPhone Dev Team, however, have given us a pre-Halloween surprise: they updated the jailbreak tool redsn0w to simplify the hacking of A4 iOS devices.
That means that owners of the iPhone 4, iPod touch 4G, and iPhone 3GS (pre-A4) are in luck. The instructions below will help you to break down the walled garden of iOS 6, and install the jailbreak app hub Cydia.

Update your device to iOS 6

The first (obvious) step is to be running iOS 6

If you aren't yet on iOS 6, this is the first step. The fastest way is to connect your device to iTunes, and follow the prompt to update.

Download Redsn0w

Redsn0w 0.9.15b1 is available at the following links for Mac OS X and Windows. Windows users will need to run it in Administrator mode. The Dev Team also advises Mac users to CTRL-click and choose open, but we found success by opening normally.

Follow the instructions

redsn0w's instructions are straightforward and clear

The directions in redsn0w are straightforward, so make sure your device is connected, open the app, and follow along. The first thing it will ask is to enter DFU mode, which involves holding and releasing the power and home buttons at precise times. Don't worry, though, as redsn0w guides you through the process.

Install Cydia

Now it's much easier to get Cydia on your iPhone 4

Unlike in earlier iOS 6 releases, redsn0w now automatically installs Cydia. When redsn0w's process completes, you'll see the jailbreak app store waiting for you.

Booting

This is a tethered jailbreak. That means that every time you reboot, you'll need to connect your device to a PC and re-run redsn0w. For each tethered boot, just select Extras > Just Boot from the redsn0w menu.

Re-restoring

The developers left a bonus in this version: the jailbreak tool lets you "re-restore" to other firmwares. As long as you've saved your SHSH blobs (device identifiers stored locally or on a server) from a previous jailbreak, you can perform a clean restore to or from any version of iOS 5.
It may be some time until owners of newer (A5 and A6-based) iOS devices are able to jailbreak, but we'll keep you posted as soon as they're available. You can read more at the Dev Team's source link below.
Source: Dev Team Blog