Coat the rattan furniture with a spray bottle filled with warm water. Completely coat the piece with the water. Leave the chair outside for 48 hours, or until dry. The water restores the natural elasticity of the rattan and fixes any dry or brittle spots.
Soak a towel in warm water and place on a sagging seat. Rattan sags and repeated use will break down the seat. Leave the towel in place overnight and remove the next day. Let the furniture dry naturally over several days.
Repair minor chips and gouges in the wood surfaces of the furniture with wood putty. Fill the damaged spots with the putty and let dry overnight. Sand the putty with fine-grit sandpaper until smooth. Rub a wood color stick over the repair, making it blend with the rest of the piece.
Clean the non-rattan surfaces with a mixture of liquid dish soap and warm water, applied with a soft sponge. Rinse the sponge in fresh water and wipe off the soapy residue. If wood areas still look dull and faded, clean with a wood oil soap.
Mix powdered oxygen bleach and warm water in a plastic bucket, following the ratio recommended by the manufacturer. Dip a scrub brush into the solution and scrub the liquid on mildew or mold. Rinse the area with fresh water applied with the scrub brush and let dry overnight.