The items we needed were a 6 foot 1x8 board, spray paint stain, house numbers, and a sharpie. We sprayed the stain on one side of the board and wiped it down with a disposable cloth. We let it sit overnight and then came back to the project the next day. We measured out each inch, starting with the bottom of the board representing 6 inches. That way we can hang it 6 inches off the ground and it will still be true to life. We drew a line at each inch with the sharpie and then nailed a number on the board to denote each foot. Here is the finished product:
close up of detail
I'll be drawing in skinnier lines to denote Dutch's height, and I'll write the date and his age on the line. Pretty happy with the finished product!