Below is a concise, step-by-step guide to backing up, installing, and improving visual quality for Pro Evolution Soccer 2013 on PSP (also called PES 2013 Portable). I assume you have a PSP (or PPSSPP emulator) and a legally obtained game/ISO/CSO.
Download your "Extra Quality" save data (usually a folder named ULES01595 or ULUS10617 ). pes 2013 psp save data extra quality