Leather is made from the skin of animals and is considered hygroscopic, meaning it will absorb and retain moisture. You may have noticed that your leather watchband, after wearing it for a while, becomes moist and sometimes can smell a bit rank. This is common with many leather watchbands, especially if you wear them while performing activities that produce perspiration. White leather watchbands will become visibly dingy if not properly cleaned periodically, because dirt and grime will show up faster on white leather. Properly cleaning and applying leather-preserving ointments will ensure that your white leather watchband stays supple and clean throughout its life.
Remove the watchband from the watch face. Typically, two pins hold the watchband onto the watch face, and, when depressed, they can be removed. Some watches may require professional service or a different method to remove the band
Moisten a soft cloth and lightly wipe any dirt away from the leather surface. Do this for both sides of the leather band.
Apply a saddle soap to the band and rub it in thoroughly. Follow the instructions for the specific type of saddle soap you use, because the types can vary slightly.
Clean off the band with a moist towel and dry thoroughly with a dry towel. Apply a white leather conditioner, such as Old Number 7 Extra Fine Beeswax, which helps to naturally condition and waterproof the leather, or Obenauf's White Jaguar Leather Cleaner and Conditioner.
To avoid a dingy appearance, clean your leather watchband once a month if you wear it often.
Test any leather cleaner prior to using it. Leather cleaners and conditioners can change the colour of some leathers and make white leathers appear either brighter or darker.