For cotton and polyester: Shake or gently vacuum garment to remove loose particles and chalk dust. Place garment stain side down on an old towel or paper towels. Gently dab rubbing alcohol on the back of the stain. Chalk residue should transfer onto bottom towel. If stain persists, pre-treat with liquid dish soap (such as Dawn) and machine wash according to garment care label.
For washable silk and wool: Shake or gently vacuum garment to remove loose particles and chalk dust. Apply a gentle liquid laundry detergent, such as Ivory Snow, and let sit 10 minutes. Apply small amount of water and rub until suds form. Flush with cool water and air dry. If stain persists, take garment to a dry cleaner.