Measure 2 inches away from the end of your driftwood and drill a 1/8-inch hole through the wood. This is a pilot hole for the screw that will attach the driftwood to the wall. Measure 16 inches away from this hole and drill another 1/8-inch hole. Continue drilling these holes every 16 inches until you've reached the end.
Measure 2 inches away from the first 1/8-inch hole and drill a 3/32-inch hole every 4 inches. These are pilot holes for your screw hooks.
Locate studs in the wall with your stud finder and position your driftwood against the wall so the 1/8-inch holes are over the studs. Place your level on top of the driftwood to ensure it is parallel with the floor.
Screw the driftwood to the wall using your 4-inch screws and screw the screw hooks into the 1/8-inch holes. These hooks will hold your hats, jackets and scarfs.