Wow. You know how many tutorials there is on how to do this? All you ahd to do was simply click the search button....that easy. But sicne im soooooooo nice I guess I will tell you. You can either use a program like theme cycler in the downloads section, or manually boot into recovery mode(you have to have a custom firmware) and toggle usb on for flash0 and paste the files there. Backup your flash0 first though.
http://www.pspbrew.com/forum/viewtopic.php?t=7725
