Description

From the 3DS Home screen:  
-Press L+R to activate the camera  
-Tap the QR button on the touch-screen  
-Line up your camera with the QR code (this image)  
-Press A  
-Press A
 
Dont forget to turn on the 3D switch.
 
This is the image I used: https://derpiboo.ru/437432

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