Here is a very simple tutorial to how to make a safe jailbreak process to your device on iOS 5 Beta 7 with Redsn0w 0.9.8b7b .Also you in this post you can download iOS 5 Beta 7 IPSW if you are not develpoer.
Step 2 : Download iTunes 10.5 beta 7.
The firmware will then be identified by the program, as shown below:
Step 4:Select “Install Cydia” Then hit Next
Step 5: Another screen should now pop up. Before clicking “Next”, make sure your device is both turned off and plugged in, as instructed by Redsn0w.
Step 6: You’ll now be instructed to enter DFU mode. As shown below, Quickly hold “Power” button and then while holding the “Power” button, you will now have to hold “Home” button too. Now after few seconds release “Power” button but keep holding “Home” button until installation begins.
Now your finish ,don’t do any thing ,Redsn0w does the rest of the work for you.
As we mentioned above, this is a tethered jailbreak, meaning that it will require you to connect the phone to a computer running Redsn0w whenever you power up the phone. In order to do that, open Redsn0w and choose the option “Just boot tethered right now”, with your phone plugged in.
Download iTunes 10.5 beta 7.