If your doors and windows have been oiled within the past one to two years, and the surfaces have not lost their finish, we recommend that you use the following treatment.
Follow these four steps:
Lightly sand with sandpaper
Brush off loose particles
Clean with a suitable agent to prevent buildup and discolorations
When the surface is clean and dry, apply a suitable oil treatment. Use a brush or sponge to apply the oil. Remove excess oil with a lint-free cloth to avoid shiny spots. For dry sanding on non-degraded surfaces, use 180 to 220-grit sandpaper.
Always remember to sand along the grain of the wood and not against it, to avoid visible scratches.