There are two main ways of folding this model. When folding from a grid, one can create the twists one by one. Folding this way is quite pleasant and this is
the method I show during workshops, but it results in the grid being visible on bricks’ faces. The other method is first constructing a clean precrease and
then collapsing it by pushing the whole model together. This method requires more work but results in a model whose bricks have no unnecessary creases on the
front side and only a few extra creases on the back. The pictures below show how the clean precrease can be constructed using only origami methods and then
collapsed into its final form.
Thick paper (80-120 gsm) is recommended for this model, especially for the clean collapse. Without enough stiffness, it may be very difficult to get the
collapse right. The model shown here was folded from a 24 cm sheet. At this size, the central part was quite difficult to reach with my hands as I was trying
to put the creases into the correct mountain-valley assignment. Even though usually folding with a larger grid size makes a model easier to fold, in this case
perhaps a smaller sheet (20 cm or so) would be easier to collapse.