Salt water should not be used for cleaning open wounds.Tincture iodine can be used and is advisable.Hydrogen peroxide
can be used(with caution).Yellowish discharge means the wound is infected.I suggest to get a tetanus toxoid injection
.Remove the bandage & apply betadine
ointment and roll a gauze around your wound.Donot wet your foot.If you have fever or if the discharge is more you might require a medical opinion
.Hope this helps.Take care.