Hi,
i'm not so expert, but i can tell you something.
If you want to use this program, first you must have a custom firmware (for example 3.71-M33 ) on your psp, otherwise you can't load homebrew. (if you don't know what i mean, just check it on google. You'll find million of threads

)
If you already have the custom firmware, just follow the "read me file" (you'll find it in the Furikup-0.1a folder):
Copy the contents of the MS_ROOT folder to the topmost folder on your PSP memory stick. If you've done this correctly, you will end up with a set of files within the folder
/PSP/GAME/Furikup
on your memory stick.
If you're using custom firmware, with the default kernel set to v1.5, you may wish to copy the folder to GAME370 or a similarly-named folder. We assume that if you know about how to change your default kernel, then you'll understand what you need to do.
You also need a voip account with one of the several provider you can find on internet. (for more infos look
here and
here)
If you have problems, just ask here

Best regards