Always check your topper’s label for care instructions first. However, most toppers respond well to common methods used to remove stubborn stains from memory foam. Mix equal parts gentle liquid laundry detergent with water and use a light-colored washcloth to rub the stain with the mixture. Let sit for 30 minutes before using a damp cloth to blot up the solution. Use a clean, dry towel to blot dry. You can use the same method with baking soda as well, mixing equal parts with water.