17.
Repeat the steps #13-16 for three more times.
We now have 12 crease lines.
18.
Rotate the paper by 45 degrees.
Prepare to valley-fold.
Have you got a Brook in your little heart, Where bashful flowers blow, And blushing birds go down to drink, And shadows tremble so -- And nobody knows, so still it flows, That any brook is there, And yet your little draught of life Is daily drunken there -- Why, look out for the little brook in March, When the rivers overflow, And the snows come hurrying from the fills, And the bridges often go -- And later, in August it may be -- When the meadows parching lie, Beware, lest this little brook of life, Some burning noon go dry!