You need a USB device thats compatible with the PS3 so anything like a pen drive or a PSP will be fine, you'll need to create a folder called PS3 (note the capital letters) inside there you need a folder called SAVEDATA (again all caps) in there you place the downloaded save extracted so that the folder you see starts BLES or BCES etc with the save data inside that, then plug it in and go to the saves section of the XMB and it should list the USB device you have connected and if you click it it should list you the saves you have, then just hit triangle and hit copy, assuming its not a copy protected save ofc