Take a 12"x12" piece of thick paper or card and fold into nine 4"x 4"squares. Cut out the top and bottom middle squares and you should be left with an H shape.
This shape will fold all ways...up,down,side to side...until you have a 4x4 book so it is up to you how you fold it up and decorate the squares. An added bonus is it will fit into a CD case when its folded.
(I've done a pic of a rough template) Have fun...!