Things You'll Need
Instructions
Download the theme of your choice to your hard disk. The theme that you choose should be in .ctf format.
Plug your PSP into the computer in USB mode. Open the PSP file directory through your computer.
Open the "Theme" folder in the PSP.
Drag the downloaded theme to the folder.
Unplug the PSP, turn it on in normal mode.
Select "Theme Settings" on the main menu. Select "Theme" from the submenu. Scroll down on the next screen until you come to the theme that you just installed. Click on it.
Select "Yes" when asked if you want to overwrite the existing theme.