Use a tape measure to measure the length of the sides of the golf cart. Jot the numbers down, but add 1 foot of length to each end to accommodate for the bow and stern of the ship-to-be. Measure the height of the cart but subtract 1 foot to accommodate for ground clearance.
Lay one sheet of ¼ inch plywood flat and trace the outline of one side of a pirate ship which, generally speaking, is shaped like a banana with one end tip removed. Make the tracing with the carpenter's pencil according to your measurements of the golf cart. Consult pictures of pirate ships to gain a better understanding of the ship's shape.
Cut the ship shape from the wood sheet using a power saw, following the pencil tracing. Repeat the above step for the remaining sheet of wood to create the other side of the ship. Use a paint roller to paint one coat of brown paint over each plywood sheet, which gives the wood a more weathered look. Once this coat dries, use a small brush to paint small horizontal lines of black paint inside the interior of each ship shape to create the illusion of individual wooden beams.
Hold each side of the "ship" flat against the cart, positioned like a ship. Note where the bars are on the front and back of the cart and make two small dots on each "ship" side to indicate the bars' position. Drill two small holes into each pair of dots; loop a 20-inch plastic zip tie through each pair of holes and anchor each "ship" side to the front and back of the cart using the ties.
Trace a skull and two crossbones on white felt using a fabric marker. Cut out the shapes and use a spray adhesive to coat a square of black fabric. Position the skull and crossbones onto the square to make the Jolly Roger, the "official" pirate flag that you can hang from the canopy on the cart as you wish.