Apple has released iOS 6 beta 2, and so redsn0w has been updated to version 0.9.13 dev 2, with support for many bugs and crashes. If you're a jailbreak developer it's probably a good idea to start updating your apps and tweaks as soon as possible to add iOS 6 compatibility. Follow along for a complete walkthrough.
Disclaimer: This release of redsn0w is meant to be a developer release and not a general release to the public. Just as you should expect bugs in a beta version of iOS, you should also expect them in beta jailbreak tools. This release does not install Cydia and is meant only for developers. If you aren't a developer, we advise you stay away.
Your jailbreak will be tethered so once the jailbreak process is complete you'll need to perform a tethered boot with redsn0w.
Once your iPhone, iPad, or iPod touch finishes booting up you will be jailbroken on iOS 6 beta 2. Keep in mind this does not install Cydia. You can use the SSH method to install and test your apps and tweaks. You can also use this method to install Cydia if you'd like. But again, we advise only jailbreak developers use this version of redsn0w and the general public wait for an official release after iOS 6 drops this Fall.