Put two magnets together side wise and attach to the switch 2 in the position they'll be and flip 180 on the z axis before fitting in the adapter. Since the holes have little tolerance, it might be very hard to take them off, so make sure they're in the right position (if you also rotate 180 degrees on the y axis it won't work, so double check it). The ones in the picture were printed with ABS. Make sure you test it (my test is holding the adapter with a joycon attached vertically and shake it to see if the switch falls off) before handing to a kid.