Cool off with a backyard shower you can make in a weekend
Dig a 12-inch-deep hole for the center shower pole. Place it so the faucet handle will project outward at 45° between the wing walls.
Set the wing walls at square to each other and attach them to the pole (with three 12-inch screws each) so their legs only go 6 inches into the ground.
Check verticality with a level before tamping and compacting soil.