1. Lower the water to just below the inlets -- about a foot below the skimmers. Remove the "eyeballs" from the inlets and store in a bag for next year.
2. Drain the pump, chlorinator, multi-port valve, filter, and heater.
3. Use an air compressor to blow out all the lines going into the pool, including the fill line, return lines, skimmer lines, and main drain. Then cover the inlets and skimmer openings with rubber plugs. [Note: there is a certain technique that must be utilized when blowing out the lines, so this is just a bare bones description.]
4. Treat the water that's left with lots of chlorine shock and algaecide. You'll have to ask the pool place (Leslie's, etc.) how much you need per 1000 gallons.
5. Put a good quality pool cover over the pool and use water bags to hold it in place.
The two critical things are: Do not drain all the water out of the pool or it can crack, cave in, or pop out of the ground. You need to make sure you blow out all of the water in every pipe or hose that is above the frost line or you will have one hell of a time finding and repairing the leaks.