First, remove any mustard remaining on the fabric using a blunt knife. Try not to rub it any deeper into the fibers. Treat the stain with a heavy-duty liquid detergent and then reinse thoroughly. Soak the garment in a dilute solution of all-fabric or oxygen bleach like OxiClean.
Launder as usual in cool water. Do not dry the garment if the stain remains. Repeat the steps until stain is removed.


