first your going to need your firmware for your iPhone/iPod
Link to get Firmware http://www.felixbruns.de/iPod/firmware/
Second you will need your jailbreak program
Link for RedSn0w http://www.redsn0w.us/search/label/Jailbreak
Link for GreenPois0n http://greenpois0n.com/
Link for GreenPois0n http://greenpois0n.com/