Start by gluing the shims together, with the thin tapered end of one piece, matched up to the thicker end on the other. 

Paint the wood pieces with your favorite color paint.

Arrange them with a little bit of spacing between, and enough space for two additional wood pieces to cover the back. 

Glue the back pieces perpendicular on top of the others.

Print out your favorite saying on your computer.

Use a pencil to rub all over the back, and then trace it onto the wood by pressing firmly all along the printed letters.

Then use a chalk pen to fill in your pencil tracing and add a few freehand doodles.