Now today, they have released a developers only version of iOS 6 beta jailbreak. Since it is a developers version, Cydia is still not included but the device can be accesses using SSH or afc2. This jailbreak is tethered and Redsn0w 0.9.13dev1 is the tool that can be used to jailbreak iOS 6. There are several guidelines that you need to follow before you can proceed with this jailbreak. Head over to http://www.applenmicro.com/
How To Tutorial from http://www.applenmicro.com
I) Download Redsn0w 0.9.13dev1 from the given links.
II) Download iOS 6 beta 1 IPSW for your device. Once iOS 6 firmware is downloaded, use iTunes or Xcode to restore.
III) Highly Recommended:
IV) Run Redsn0w 0.9.13dev1 .exe file and select ‘Extras‘. Then "Select IPSW".
V) Now Browse and select iOS 6 beta 1 IPSW.
VI) From Redsn0w, click Jailbreak.
VII) Now you just have to put your iDevice into DFU mode and Redsn0w will continue the procedure. Please follow the on screen instructions to put your iPhone or iPod touch into DFU mode.
VIII) Once your device will be detected by Redsn0w it will start exploiting it. Once jailbreak is done, you will have to use Redsn0w's Just Boot tethered option from 'Extras' section in order to reboot the device. As you know it is a tethered jailbreak, if you restart you will need to connect your iDevice to Redsn0w and click on "Extras" and then "Just Boot".
Now your device will be successfully jailbroken but Cydia wont be installed. As there are many things which needs to be fixed now and which would take a lot of time before the final release, but you can access your device using SSH or afc2. Again, this is developers only jailbreak. If you don't know what you are doing, don't even give it a try.