How do I protect my dishwasher from freezing if stored in an unheated space?

If the dishwasher will be left in an unheated place during winter, have a service technician cut off electrical power, turn off the water supply and disconnect the water inlet line, drain water from the inlet line and water valve, reconnect the inlet line, and use a sponge to soak up remaining water in the rubber boot under the sump cover. This requires removing the plastic sump cover in the tub bottom to access the rubber boot. (Page 16)