Many pillows come with removable machine washable covers that you can simply toss in with your regular laundry. Once the cover is removed, or if you do not have a removable cover, follow the next steps.  Take the pillow, if it is an air pillow, close the valve completely, if it is a foam-filled pillow, skip this step.  Fill a washtub with laundry soap and warm water. Place your pillow in the tub and gently knead it allowing the soap and water to work into the pillow. Next, drain your washtub and rinse your pillow thoroughly with cold water. Squeeze out the excess water from the fabric and then hang the pillow to air dry. Do not use a tumble cycle in an electric dryer.  Make sure your pillow is completely dry before packing away to prevent mould or mildew from forming.