Building an Icosahedron (D20: 20-Sided Die)

Do you know how to build a 20-sided platonic solid?  It's not hard.
You need: 20 equilateral triangles cut out of paper or card stock and some tape.

First tape one edge of each of three triangles to the edges of another triangle to create a large triangle from three of the original pieces.  Repeat.

Next, tape a pair of triangles together, edge to edge.  Repeat five more times.
You should have 2 large triangles and 6 pairs of triangles.

* * * * *

Now, tape one pair of triangles edge-to-edge with the corresponding edge of each of the three single triangles you added in step one.  See diagram for an example.

* * * * *

Tape the edges of those triangle points to the closest edge.  Do this six times, three times on each configuration.  You'll end up with two domes that have staggered edges.

* * * * *

Finally, tape the dome-like sides together so that the points fall into the dips along the edges.

Tada!  You've done it!  Try it with paper mache, fabric, or whatever you'd like!  I plan to make an enormous throw pillow for one of my daughters who is a participant in two different D&D gaming groups.  Also, she likes squishy things.