Things You'll Need
Instructions
Download the DSx86 Windows emulator for your DS. Click on the link to the download and the file will mount on your desktop. (See Resources.)
Double-click on the zip file to open it. Place the microSD card into the card reader and plug it into your computer's USB port.
Copy the following files onto the microSD card: "dsx86.bmp," "dsx86.ini" and "dsx86.plg." Drag-and-drop the files onto the card's icon to copy them. Place an EXE file on the microSD card.
Remove the card reader from the USB port. Slide the microSD card out of the card reader and place it into the slot on the flash cart. Place the flash cart into your DS.
Turn on the DS and select the flash card from the load menu. Click on the EXE file with the "A" button to launch it.