Disconnect and launch the game from the "Game" menu on your XMB. For PPSSPP (Android/PC): Open the PPSSPP app. Navigate to the folder where you saved the repack. Click the game icon to start.

The Ultimate Guide to SOCOM: U.S. Navy SEALs Fireteam Bravo 3 PSP Highly Compressed Repacks

Navigate to the ISO folder on the root of your Memory Stick. Copy the compressed .ISO or .CSO file into that folder.