$1911

Does anyone know how long the threads have to be.

I usually work with an entire skein of floss. If you leave the papers on the ends, fold it in half, then put a small rubber band around the papers (now in the middle), you can do it. I've not made this particular bracelet, but I've used this method and never run out of thread. When you need more thread, just undo the rubber band, pull a bit out, then re-fold and replace the rubber band.