make sure u have a usb ...

right this is what u do ....

go too mw2 and start up a single player gamer when it starts press start and click save and quite

once uv done dat go too ur harddrive and move that single player file over to the usb

plus ur usb in ur pc, download something called USBXTAFGUI Type it on google and once u dwnload dat u go on it and open device and find your profile and go into ur gamesave and extract it too ur desktop by using winrar and den u dwnload modio aswell btw and open up modio once u ddwnloaded it and move tht file into modio and den it will have the profile and once uv done dat click mod file den mod ur file too wah ever u want and den save it and rehash an resign and once u done dat delete ur orignal file dat was in ur usb and inject the modded one from ur desktop and unplug ur usb an put it into the xbox and start up mw2 den select ur usb storage and start up ur campagin hope dis helped guys