<ul>
<li>Start from RURmRvDvLvLvUm
<li>Close the <i>lid</i> by turning 180 degrees the two adjacent horizontal tiles on the right
<li>The two stacked tiles prodruding from the resulting cube can be opened by changing their hinging
side
<li>Insist in opening these two tiles untill they become coplanar, resulting in a 1x2x2 3D structure with
a pair of internal adjacent tiles, one of which becomes a flap
<li>Turn 90 degrees the newly created flap into the final shape
</ul>