(this is also currently entered in the game.life challenge, so please vote.)
Step 1: Materials
1 nintendo DS or DS lite (I am using the DS lite)
1 XACTO Knife
1 sheet of sticky photo paper or computer skin paper
1 R4 DS card with a micro SD card http://www.r4dsshop.com/
1 Micro SD card reader
And thats it!
Step 2: The Hard Step
Once they are downloaded, unzip the folder, and look inside of it. You will see three things; installinstructions.txt, MINIVMAC.ini, and a folder named vmac. Plug in your micro sd card to your computer by way of adapter, and open it. (If this is a new micro sd card, then put it into your R4 card, and plug it into your DS. Power the DS on and it should download a few things to the card. Then, plug it in to your computer.) Drag the files "vmac" and "MINIVMAC.ini" into the root folder of the memory card. The root folder is not really even a folder, but just the main thing that opens when you click on the memory stick icon. DO NOT DRAG THE FILES INTO ANY FOLDER ON THE CARD.
Step 3: Testing
it should boot mac os7. If it doesn't, please comment below.