Simplicity of Iris Folding
Square

Color 1:  1, 5, 9, 13, 17 21, 25, 29
Color 2:  2, 6, 10, 14, 18, 22, 26, 30
Color 3:  3, 7, 11, 15, 19, 23, 27, 31
Color 4:  4, 8, 12, 16, 20, 24, 28, 32