Well first of all you are going to download the PS3 Save Resigner and load up the application, it should look similar to below You are going to need to extract your Account ID from one of your own save games to do this select the button that says Or load from param.sfo and enter your removable device or desktop save should be similar to below After that we click save as profile XX for now we will save it as profile 1.Now to resigning it is very simple we load up the param of the other user,Example downloaded save from gamefaqs should look like the below image when loaded Now so that it works under your own personal account under select a profile select profile 1 then the resign button under basic resigning congratulations you've just resigned your first ps3 save Where has the resigned save gone? It will be located in save directory where your original was along with a backup and the resigned now all you do is copy the folder without (original) appendix to your removable device assuming E is your primary device it will go into E:/PS3/SAVEDATA/ after that copy it onto your ps3 and overwrite if necessary. That concludes the tutorial this was 100% written by so thanks welcome. Video tutorial
you can also get other peoples trophies via this if you wish theres a whole thread here Guide: All Instant Platin Games For Xploder / CFW but sony doesnt give toss about trophies never have