Dust off the chair with a soft, dry white cloth. Rub the cloth over the entire surface of the chair, as well as in the crevices, to remove dust and loose dirt.
Fill a bucket with ½ gallon warm water. Add a few drops of neutral soap and mix it up with your hands.
Dip a clean, soft white cloth into the soapy water. Wring the cloth out well so it's only slightly damp.
Wipe down the entire chair with the rag. Rub gently to avoid damaging the leather. Rinse and wring out the rag frequently.
Dry the chair with a clean, soft cloth promptly after cleaning to remove any excess moisture.