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You can also fill the sink with water. Use a few cups of water or just enough water to scrub and clean the insoles. Put a few drops of liquid detergent in the water. You can also use liquid hand soap if you do not have detergent. You can also use a clean cloth to scrub the insoles. Gently scrub the insoles to remove dirt and stains. If the insoles are made of leather, use a cloth dipped in the water and soap to dab the insoles clean. Do not get the insoles too wet, as this could warp the leather. Once you have cleaned the insoles well, use a wet sponge or another clean cloth to remove any excess soap on the insoles. Put the insoles on a towel to dry overnight. You can also stack the insoles in a dish rack or clip them to a clothesline to dry them. Make sure the insoles are completely dry before you put them back in your shoes.
Fill a basin with warm water. Add soap or liquid detergent. Use a soft brush to scrub the insoles. Rinse the insoles. Let the insoles dry overnight.