These Sferra Celeste pillowcases are super easy to use. Just put them on your king - sized pillows and enjoy the soft and crisp feel. When it comes to cleaning, machine - wash them in warm water on a gentle cycle. Don't use bleach because it can damage the fabric and make it yellow. Also, avoid fabric softener. Wash dark - colored pillowcases separately to prevent color bleeding. For drying, use the low - heat tumble dry option and take them out while they're still a bit damp. If they need ironing, use the “cotton” setting on your steam iron. With these tips, your pillowcases will stay in great shape for a long time.