Once you have all those requirements, start following these steps to jailbreak iOS 5 beta 1.
Run sn0wbreeze-v2.8b1.exe inside sn0wbreeze-v2.8b1.zip
You will see a warning that this software (sn0wbreeze) is not for commercial use. If you have bought this software (sn0wbreeze), demand a refund. No guarantee for any damage on equipment which caused by sn0wbreeze.
Click OK and you will see credits to the guys who involved in building sn0wbreeze tool. Click Close Credits to close credits.
Welcome to sn0wbreeze. sn0wbreeze version 2.8 [BETA 1] For 5.0b1 [9A5220p].
Intended only for Developers!
This is a tethered jailbreak via iBooty
Hacktivation is disabled
Click the Next button (Blue arrow on the right bottom corner) to continue.
Please select the iOS 5 IPSW file that you have downloaded before by either clicking the Browse button or drag the IPSW file into sn0wbreeze.
Locate and select the IPSW file, then click Open. Make sure that you select the correct IPSW file for your device.
Please wait a moment while sn0wbreeze identifying IPSW. A message saying Invalid IPSW file will appear if you select wrong IPSW file.
Once IPSW verified, click the next button again.
Please select a mode. Simple Mode and Expert Mode. This is how you will configure the custom IPSW file. Since we will not find many options on Expert mode, please select Simple Mode instead then click the next button.
sn0wbreeze will start building custom IPSW. While waiting for the IPSW to finish being built, you will be offered to play PacMan. Playing pacman doesn’t affect to sn0wbreeze which currently building custom IPSW. Or you can simply do nothing and wait until sn0wbreeze finish building custom firmware.
Once the process finished, sn0wbreeze will say Done!.
sn0wbreeze seems to have successfully created custom IPSW for you.
The custom IPSW file should be located on Desktop named sn0wbreeze_DEVICE-FWVERSION.ipsw
Clicking OK button will get you into onscreen instructions to put your device into DFU Pwned mode using DFU Pwner. The steps are exactly the same with entering normal DFU mode guide. This software will help your device entering Pwned DFU mode so you can restore the custom firmware later.
Once your device has entered pwned dfu mode, characterized by black screen on device and sn0wbreeze alert saying the device is now in PWNED DFU STATE. If you failed to enter PWNED DFU STATE, just repeat the instructions to enter pwned dfu mode once again.
Now, open iTunes and hold-down SHIFT button on keyboard while clicking restore button on iTunes.
Then, select the custom IPSW file which created by sn0wbreeze. The IPSW file should be located on Desktop with filename sn0wbreeze-xxx_xxx.ipsw (xxx refers to idevice model and iOS version).
Wait until restoring process has finished and you are ready to activate jailbroken iOS 5 beta 1.