Casio G-Shock watches come with a variety of wristbands. The leather and fabric wristbands can absorb moisture and in doing so become rather smelly. While you can remove the smell from a fabric wristband by removing the watch casing and putting the strap through a normal wash, the leather straps require a little more care and attention to remove the smell.
Insert a spring bar removal tool between the watch casing and the end of the watch band. Catch the spring bar in the fork of the removal tool and depress the spring bar. Move the spring bar away from the housing and pull out the watch band end. Repeat this on the other side.
Mix some water with soap. Rub the mixture over the watch band with a cloth. Do not saturate the cloth as you do not want the strap to absorb too much liquid. Clean the strap off and leave it to dry.
Rub the inside of the strap with a toothbrush to clean away any unwanted debris.
Clean off the band with a towel. Apply a commercial leather conditioner to the band according to the manufacturer's instructions. Clean off the band with a dry towel.
Realign the strap end with the watch casing. Insert one end of the spring bar into the watch casing housing. Depress the other end of the spring bar with the spring bar removal tool Slot the end of the spring bar into the watch casing housing slot. Repeat the process on the other end of the strap.