You earn green vouchers for accomplishing certain things in the game, you then have to convert them into friend credits. You do this by adding someone to your wii address book who also has friend vouchers on their MP3 save data and swap with them. Once they have been swapped they become friend credits that you can use for unlockables, etc.
I think I have about 18 to swap with you if ya want, just PM me your wii number and I'll reply with mine.
I think so since thats the only way I've ever done it. I know you both have to have MP3 save date on your wii, I'm assuming that you both have to have friend vouchers.
You don't need to have Friend Vouchers to receive Friend Credits. Just get each other's friend code and there should be a button that says "Send a friend voucher" or something. Unfortunately, I don't trust the stability of the system. PiccoloCube and I sent each other 15, but I got 7 and he got 22.
well, once the trilogy is out, i'll be doing 100% item completion again and will need a few vouchers from someone so i hope the system doesn't fail this time.