<ul>
<li>Start from RUmUvUmRDvUvDv
<li>Close into a 2x2 square with four stacks of two tiles each organized in three levels
<li>Position it such that the two East stacks have first and second floor, whereas the two
West stacks have second and third floor.
The North-West top (third floor) tile is of type <i>slash</i>
<li>Turn (down) 180 degrees the flap tile located at bottom (first floor) of the North-East stack
<li>Open in 3D with the following hinging
 <ul>
  <li>NW stack: north side
  <li>SW stack: keep stacked together
  <li>SE top two tiles (second and third floor): north side
  <li>SE bottom two tiles (first and second floor): east side
 </ul>
<li>Turn 90 degrees the flap tile (against another tile)
<li>Turn 90 degrees the newly created tile into the final shape
</ul>