Clean the furniture with warm soapy water and a scrub brush to remove dirt, grime and mildew. Air-dry the furniture completely.
Sand the surface of the furniture with fine-grit sandpaper to remove rough or weathered spots. Sand with the grain of the wood.
Wipe the wood with a tack cloth to remove dust.
Apply a coat of teak oil with a paintbrush. Wipe any excess oil from the furniture with a soft cloth. Be sure to coat the back and bottom surfaces of the furniture as well.
Allow the furniture to dry. Apply additional coats of teak oil until the wood is the color that you prefer.
Repeat this process at the end of each season.
Power-wash the furniture to remove dirt and mildew that has built up on the furniture. Be sure to clean the back and bottom of the furniture, too. Allow the wood to dry completely.
Sand the wood lightly with a fine-grit sandpaper, removing any rough areas.
Wipe the furniture with a tack cloth to remove dust particles.
Apply a wood sealant to all surfaces of the wood with a paintbrush or soft cloth. Wipe the surface with a dry cloth to remove excess sealant.
Repeat this process every two or three years, or when the wood begins to fade.