<ul>
<li>Start from M_RRmURvLmRvRU
<li>Rotate 180 degrees with a valley fold the two East adjacent tiles
(the two extremal tiles in the flat 2x2 square)
<li>Lower the upright flap 90 degrees against the other flap
<li>Rotate 90 degrees the two adjacent tiles pointing down, one of them will
stack against the two stacked flaps
<li>End up with a 2x2 square  with two stacks of two tiles in the East positions,
a stack of three tiles in the North-West position and a single tile in the South_West
position
<li>Open in 3D with the following hingings
 <ul>
  <li>Keep the two tiles in the NE stack together
  <li>Hinge the SE stack about the East side
  <li>Hinge the two top tiles in the NW stack about the North side
  <li>Hinge the two bottom tiles in the NW stack about the East side
 </ul>
<li>The resulting structure is contained in a 1x1x2 box and comprise a pair of stacked tiles
<li>Rotate 90 degrees a group of three mutually orthogonal tiles
<li>Rotate 90 degrees a newly created flap into the final shape
</ul>