That guide means that you need the .3DS version of the BigBlueMenu or DevMenu before installing the CIA of that program. If you get the 3DS of the installer program you can install all those CIAS. If you still want to convert CIA to 3DS just download the 3DS to CIA converter and you will find the option in the menu. You won't need anything else, just the CIA and the converter. It will tell you what to dofrom maxconsole guide on istalling .cia files on the new gw3.0
Step 1: Put your .cia manager on the root of your Gateway Red SD Card. If yours came in .cia format, you need to go back and download it as .3ds for now. Put the card back in when you are done.
all my eshop games are .cia files sooo I take it i need them to be .3ds now to install and was wondering how to convert back