Brush dried salt from the cloth boots with a soft-bristle brush. Use light pressure and gently brush as much salt off the cloth as you can.
Mix 1 tbsp. white vinegar into a quart of warm water in a bowl. Dip a section of a clean cloth into the mixture.
Rub the wet area of the cloth gently into the remaining salt stain. Inspect the stain after 30 seconds. Add another tbsp. of vinegar to the water if the stain remains. Continue rubbing the stain with the vinegar mixture until it disappears.
Rinse the cloth boots by wiping them with a damp cloth, removing the vinegar solution and the salt from the footwear.
Place the boots near a heat register until dry.