Scrape off any excess mustard with a plastic knife. If you don't have a plastic knife, use a blunt butter knife instead.
Fill a container with 2 cups of warm water and 1 tbsp. of liquid dish detergent. Mix well.
Dip a clean, white cloth into the liquid mixture and dab the dampened cloth onto the stain.
Dab the stain with a dry section of the cloth until you absorb the liquid.
Continue to moisten and blot the stain dry until you cannot see the mustard anymore.
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