(1) Take a square piece of paper,
white side up, and accordion
pleat it into fourths.

(2) Fold the top left corner down.

(3) Fold the right end of the strip
down to meet the folded edges.

(4) Now fold the strip up, making
the bottom flush.

(5) Fold the strip down to the right.

(6) Mountain-fold the upper right
corner behind, and you're done with
one unit!

(1) Slide the end of one unit into
the side of another, as shown.
The flap should go in between the
layers of paper, and crease lines
should line up.

(2) It takes three units to make a
"corner" of the polyhedron.
Slide the third unit into the second
unit, and slide the first into the
third.

(3) This is what you should see.
Notice how exactly half of
each unit was used to make this
"pyramid." Continue adding units
to this to make your polyhedron.