Sand both pieces of wood entirely, including the sides. Start with 80 grit sandpaper then work up to 120 grit. Wipe away the dust with a damp rag and let dry.
Coat the top of the wood with a dark wax, rubbing it in circular motion with rag. Let it dry and the repeat the process.
Lay the wood face down on a drop cloth. Place the metal legs in center of wood. In case the metal base is slanted or bent, use a shim to make sure the legs will sit level. Double check with a level.
Place washer over screw and drill it into place securing the base of the wood. Use a level to ensure evenness, tighten or loosen the screws accordingly.
Joanne Palmisano is the author of Salvage Secrets (W.W. Norton, September 2011). Visit her blog, also called Salvage Secrets.