For games, format your mem stick using the PSP. Drop PSP ISOs on the folder ISO of the mem stick and you're ready to play it on the PSP.
Ok to put isos all you have to do is put the .iso/.cso file in the ISO folder on the root of your memory stick. To put emulators you put the emulator file in the GAME folder. Then, you put your backups in the ROM folder inside the emulator folder. Hopes this helps.
first of all, make sure you format your memory stick from the PSP to put all the folders etc in place. you connect your PSP to your computer via USB. Your backups of your UMD game ISOs go in ISO folder. You can also put the .cso (compressed isos) in there. PS1 Games go in PSP > Game > GameName Home brew goes into ... PSP > then GAME150 or GAME380 depending on what version it needs. You will probably need to install the 150 addon to make homebrew work properly. once its in the right folders, it shows up under game > memory stick
Well I don't know if I just got lucky but I didn't format my card and it works fine. I don't see any reason why I would hurt though.
