I sewed the snap contacts on a shirt with the conductive thread, and used the thread to connect the neopixel 12 LEDs ring. I also soldered the second part of the snap buttons to the flora  pads, so I now can snap it on and off. And it works pretty well :)

Side note: I kept an other shirt underneath because I didn't want my body to make a short and damage the Neopixels orthe FLORA board.