With a soft shoe brush, gently brush away any dirt, dust and debris from all areas of the shoe, including the leather and the sole. It's essential to use a soft shoe brush and not a regular brush, because anything with tough bristles could scratch the leather. If you don't have a shoe brush, then you can use a soft cloth.
Mix warm water and about 1/2 tablespoon of saddle soap in a small bowl.
Using a soft cotton cloth, scrub the shoes gently with the water and saddle soap mixture wherever there are scuffs or scratches on the leather. A few minutes of rubbing with the cloth and soap should smooth away scuffs and scratches that aren't set too deep into the leather. Deep scuffs or scratches need to be fixed by a professional.
Add 1/2 teaspoon of tan waterproofing leather shoe polish to a clean cotton cloth and gently apply it to the leather. If it's the first time you're polishing the shoes, apply a tiny amount to an area of the shoe that's not easily noticed. Let the polish fully dry in that one area to make sure that the polish works well with your shoe color. Be sure to apply the shoe polish evenly.
After polishing, let the shoes dry for a few hours before wearing them.