• Start from RRmRmRRmRvLmRv
  • Close it into a flat 3x1 sequence of stacked tiles: two in the northern position, four in the central position, including the two flaps (hinged about their north side), two in the southern position
  • Open in 3D by hinging the central and southern tiles about a vertical (east or west) side, the northern tiles about the north side.