Wipe the boot with a clean, dry cloth to remove any dirt or salt still on the boot. There may be small fragments in the crevices of the boots; therefore, wipe the boot from top to bottom and along the seams.
Mix one part white distilled vinegar and one part water in a spray bottle. The solution should be mixed well before applying to the boot. Test a small area of the boot to ensure the solution will not discolor the fabric.
Spray the area directly with the solution. Use a clean white cloth to rub the solution into the area on the boot until it disappears. Avoid using paper towels to rub the area because the fibers from the paper towel may rub off onto the fabric, creating small white balls that are hard to remove.
Wipe the wet area down with a dry towel and set the boots aside to dry completely. Repeat the process if the spots are still visible once the boots dry.