you use game code loaders like gecko and ocarina, if you are using a disc look on wiicodes and you can create your .gct on the web site or copy paste the codes you want in to a code manager and create your own gct files (look on youtube)then copy gct files to sd:codes. this can cause problems for a beginer but you will get the hang in a day or two. so in most cases i think the easiest way is to use the ocarina plug in in usb loader gx or configurable usb loader, usbloader gx has a download and creat gct option built in so you dont really need to search or creat or copy paste any thing. on cod games change the hook type to ossleepthread if your wii freezes you probably have a bad code. some codes require an activator like a button stroke to be manually designated. thses sometimes will not work thru the automated plugin. if it doesnt work it might be patched alot of codes on the net are old obviously hope that helps