Just download redsn0w
extract the folder to your desktop
open the redsn0w folder
drag the "redsn0w,exe" to your desktop.
right click; click "run as administrator"
Plug in iPhone
Click the "jailbreak" button.
shut off device completely.
Enter DFU mode (hold both home and sleep/power button simultaneously for 10 seconds. Right when you get to 10, let go of the sleep/power button but make sure you dont let go of the home button for an additional 15 seconds)
Wait for device to reboot.
If you get a message saying that it is a "tethered jailbreak" (very important) then you will have to go back
click "extras"
Shut off device again, and enter DFU mode again
then click "Just boot"
wait for device to boot up.
You must do this on every reboot. that is what a tethered jailbreak is. that is why you should have stayed on 5.0.1 so you could enjoy an untethered jailbreak.