2. Download Redsnow here for Windows and here for Mac
3. Open Redsnow
4. Plug in your device and turn it off.
5. On Redsnow, click "Jailbreak"
6.Now it will get you into DFU Mode. Follow the directions. If you don't get it on the first try, try again
7. Once, you're in DFU Mode, Redsnow will jailbreak your device
If you are jailbreaking on iOS 4.3.4 or higher, then this jailbreak will be TETHERED. After you jailbreak, make sure you go to Extras- Just Boot, to boot your device. Every time your device runs out of battery, it loses it's jailbreak. You have to connect it to your computer, open Redsnow, and click "Just Boot Tethered" That way your device will be jailbroken again. For more information, visit How To Boot Tethered.