How to free unlock and jailbreak apple iphone 3g version 3.0?

these are instructions for pc i dont know any for mac go to http://blog.iphone-dev.org/ and download redsnow then go to http://www.felixbruns.de/iPod/firmware/ and select iphone 3g 3.0 and download then when redsnow is done downloading unzip and drag the folder to the desktop when the 3.0 firmware is done downloading go to control panel/folder options/view uncheck the option "hide extensions for known folder types" then go to the folder where you downloaded iphone 3.0 firmware and right click then rename the extension should be .zip or .rar delete whichever one is after the space and then change it to ipsw now the picture for it should be a cube with a itunes logo drag that to the redsnow folder on the desktop now if you have itunes 8.2 skip this step if not download it from www.apple.com plug in your iphone open up itunes 8.2 go to your iphone tab and hold shift and then click upgrade while still holding shift a file browser will come out locate desktop and then the redsnow folder and select the iphone 3g firmware located in there and then it will upgrade get a coffee or something while its doing that then after the upgrade itll reboot into 3.0 close itunes and plug your iphone into your computer then turn your iphone off (hold power then slide to turn off) now open the redsnow folder and double click the redsn0w.exe now itll open then click the browse button and browse to the redsn0w folder and double click the 3.0 firmware click next now on the bottom left corner theres going to be cydia and icy with a box next to them check cydia but do not and i MEAN DO NOT check icy(you can install that later if you install it now therell be errors later) click next read the onscreen instructions (get ready to press and hold buttons)click next and follow the onscreen directions afterwords itll start the proccess (if it crashes inbetween dont panic just hold the power and home button until it turns off the repeat the redsn0w steps)after its done click finish and your iphone will reboot into 3.0 jailbroken now go to settings and connect to a wifi network then press the home button and go to cydia (itll load then respring aka go back to lockscreen) then go to cydia again and touch manage then sources/edit/add then type in http://repo666.ultrasn0w.com the 0 is the number zero touch add then itll add it and then touch go back to cydia now touch the search tab and search ultrasn0w and find it then install it afterwords reboot and now you have jailbroken/unlocked your iphone yes wifi still works