This is the most popular method currently.
Crucial Tip: A US save file will not work on a European copy of the game, and vice versa. Most online forums provide save files for the US version (ULUS10556), so ensure your ROM or UMD matches that ID. naruto shippuden ultimate ninja impact save file
The installation process depends on whether you are playing on a real PSP console or an Android/PC emulator. This is the most popular method currently
For the completionists, the save should unlock all in-game wallpapers (including the rare pre-order bonus ones) and all cutscenes in the Theater mode. Load the Game: Open PPSSPP, launch Ultimate Ninja
The best save files have an S-Rank on every mission, including the hidden "Extra Missions" that unlock after beating the main story. This ensures all maps are available for free-roam farming if you want to tweak your build.