Step 1: Draw two triangles in pencil
(it will be erased later on) to form a
star shape.

Step 2: Draw in pen 'v's around the
edges of the triangle pointing up.

Step 3: Draw 'pac-man' symbols in
pen around the edges of the triangle
pointing down.

Step 4: Erase the pencil drawn lines,
and you are done.

Result: Take a moment to look at
the illusion. How many triangles do you
see? Do you see 2? You're wrong. There
is none. Because of the shading and
format of the shapes, it makes your
brain draw extra lines and make it look
like two triangles.