1. Download the OS X if2a binary package here: if2a-0.94.4-MacOSX.tar.bz2
2. Double-click on the file which should now be on your desktop.
3. Double-click on the directory which should have been made from the archived file.
4. Drag the game you wish to flash into the if2a-0.94.3-MacOSX folder on your desktop.
5. Open your Terminal.app (path shown in picture below, and no you can't have copies of my apps).
6. In your terminal, you want to first issue this command to get you into the right directory:
(Cut-n-paste will work fine for this task.)
7. Now your ready to make your command line for if2a to write your game to the flash card. There are many options available at this point, but I'm just going to show you how to write a single game with no loader on the flash cartridge (which is pretty standard usage).
My command line to burn Pokémon Emerald to my flash cart would look like this:
./if2a -n -W trm-pmeu.gba
Your terminal colors may vary, I changed mine. Your game title and/or filename maybe different then mine also. This is the most basic way I can explain how to use if2a to you, if even this is not helpful, there is really nothing more I can do.
if2a Homepage: http://if2a.free.fr/
Bored? view my very un-updated website.