Mix a very small amount of dish soap (one-eighth of a cup should be sufficient) into one of the bowls of warm water. By opting for nontoxic soap, you’ll avoid chemicals found in harsher detergents that can damage the quality and color of the leather.
Next, dip one of the cloths into the soapy water and gently wipe down the leather in the direction of the grain. If you can’t visually determine the direction of the grain, don’t worry: Simply keep your motions gentle and consistent.
Finally, dip a second cloth into the clean water and carefully wipe down the leather, following the same direction and pattern. Make sure your cloth is only damp, not soaking wet, as too much moisture can create further damage.