Scrape off the spaghetti noodles using a dull butter knife. Remove all noodles from the fabric.
Blot up excess tomato sauce using paper towels. Continually replace the paper towels as tomato sauce transfers onto them.
Douse the remaining stain with an aerosol laundry pre-treatment stain remover. Let the pre-treatment solution permeate the stain for one minute.
Launder the fabric promptly with 2 oz. of oxygen-based powdered bleach. Oxygen-based bleach, unlike chlorine bleach, won’t discolor the fabric. Use the water temperature setting and machine cycle specified on the fabric’s label.
Hang the fabric outdoors or lay it flat to air-dry.