To make the sign:
Remove the boards from the pallet and arrange them so they fit next to each other. Nail them in place and reinforce them at the back with a couple of planks. Sand the boards.
Paint the boards in the desired color for the message text.
Create the design for the message. Print this out on contact paper. Cut out the letters using a Silhouette Cameo or stenciling tools.
Apply the stencils to the board. Paint over them in the desired color for the boards. Peel off the stencils to reveal the message.