From GameBrew - a wiki dedicated to Video Game Homebrew.
The Homebrew Menu is a simple launcher menu which can be used to replace the menu on several DS flashcards. This menu supports the argv protocol needed for devkitARM compiled applications to make use of nitrofs as well as providing a soft reset feature where applications can exit back to the menu. Exiting to the menu is as simple as returning from main() or calling exit(0).
Copy BOOT.NDS and the appropriate bootstrap file from the hbmenu folder in the archive.
The latest release contains bootstrap launchers for the original R4, ezflash 5, dstt and Acekard 2(i).
Copying all the files will give you a single SD card which will boot the Homebrew Menu on all 4 cards.
The bootstrap.cia file can be installed on a 3DS using FBI. This requires boot.nds on your SD card.
Place your homebrew games in the /nds/ folder.
D-Pad - Move through the list
A - Launch homebrew
FlashCard DSTT/TTDS with Firmware 1.17
Flashcard iEvolution CycloDS with firmware 2.2
FlashCard R4iMax with Kernel 2.6
- Rebuilt with latest bootloader & libraries.