Get your water balanced 2 weeks in advance of your closing.
On closing day:
1/ Vac the pool and backwash if it's a sand filter.
2/ Start draining. You'll either need to rent a pump or if your pool is plumbed with a dedicated main drain suction that you can close off the skimmer and go main drain only, you can use it to drain the pool to the proper level. You need to drain to just below your lowest return outlet.
3/Remove wall fittings and skimmer basket. Put your wall fittings in the basket, it keeps everything together for easy storage. If you have a pool light, you need to drop it. Some float, some don't. If it's a floater, find a round river rock, put it in a plastic shopping bag and tie it around the light cord at the bulb and lower it down. If you don't, you're looking at a new light in spring. You could remove it totally, but that's a bit of work and the bulb is just as safe under the ice. Remove any pool ladders and diving board, including the base. Duct tape the threads of the base's jig or use a product called aqua lube to keep those bolts from rusting. I like duct tape as it's easy to remove in spring and you can make a bit of a flag with the ends of it to avoid people stubbing their toes on those now exposed bolts coming up from the deck. At least they have a little warning.
4/ You'll need a blower for this next bit which you may be able to rent at your local pool shop or you can also ask them in to do a "line blow and antifreeze". It's far cheaper to have them do this bit than the entire closing. It also will give you some peace of mind becuase if you DIY and miss a line or piece of filtering equipment, it'll probably split requiring a repair bill in spring. If you get a pool shop in to do the blowing, they take the responsibility if anything goes wrong. Your choice here.
Anyhow, on to the blowing and I'm going to have to assume sand filter as you haven't specified. If it's a cartridge or DE filter, I'd definitely get a pro in for the blow as these two systems can vary considerably in their plumbing and design. You just have to KNOW how to approach each which is impossible to cover here. If you post back what filter you have, I can be more help there. The steps I'll outline below apply to a sand filter.
With a sand filter, remove the bottom drain cap. If it's a Jacuzzi filter, make sure you just take the cap off and not the stem. All other filter manufacturers just use a cap on the base of the tank. Let it drain. Remove the pump basket. Put your drain cap in there and any other parts you remove from the filtration equipment. Put your filter on to the recirculate position. Remove the drain plugs from the pump. There will be two, one in front and one at the side. If this is a sta rite pump, there may not be a side plug but there is one at the base of the impeller housing (big round bit behind the basket area). Let drain and put those plugs in the basket. There are still two more things to do for the actual filter tank, which should be left towards the end of your closing involving the dial valve and pressure guages which I'll mention later.
On to your salt generator. Turn off it's power. The cell should be removable. Take it out and disconnect it from the control panel. Depending on the manufacturer, you may have to remove the sensor unit as well. If it's a Chloromatic, you'll have to. If it's a Gold line leave it where it is. Clean the cell while you're at it. That's it.
If you have a heater, turn off the gas supply both inside the heater on the gas valve and also the feed line coming into the heater. Remove the pressure switch from it's copper pig tail and let it dangle from the electrical connections and open the drain cocks on BOTH sides of the heater header if equipped.
5/ Blow time. Start with your suction lines. Hook the blower up to the line leading into your pump from the pool. If you have a main drain line, blow it first. Close your skimmer valve and any in wall pool cleaner line. When you see bubbles coming up from the main drain, shut off the main drain valve while the blower is still running, then shut the blower down. That's all you can do with a main drain suction. Anti freeze is pointless. Leave that main drain valve alone until spring.
Next up is your skimmer. If you have an equalizer line (open front hole (nearest the pool)in the skimmer, use foam rope (2 ft) and stuff it down the pipe. Cap off with a T taped winterizing plug. At the equipment, open the skimmer valve and blow. You'll see a volcanoe erupt from your skimmer. Normal. Let it run until you see very little water (mist or fine droplets) come out. Antifreeze time. Use only RV or Plumber's antifreeze, nothing else. You can get it cheaper at a hardware store than at the pool shop. Pour about a liter into the suction line at the pump, where you had your blower hooked up for the main drain blow, re attach the blower and run. When you see another volcanoe at the skimmer, check it for colour ( plumber's antifreeze and RV anti freeze is dyed) If the colour looks strong you're done there. You can either T tape up what's called a Gizmo ( can be bought at a pool shop) and thread it in to the rear opening or, if that skimmer has a smooth bore, use a rubber expandable plug and then toss in a few empty chemical bottles or large plastic coke bottle. Even a block of styrofoam will do. The idea is that any water getting into the skimmer now and freezing, will crush the bottles or styrofoam and not damage the skimmer. The gizmo does the same thing but costs a few bucks. Close your skimmer valve if you have one. You're done with the skimmer, put the lid on.
If you have an inwall suction line for a pool cleaner, blow it in the same manner as the skimmer, from the same location at the equipment. T tape a plug and insert it. Hand tight plus 1/4 turn with a wrench is all you need. Same goes for all threaded plugs you use. Close that inwall suction line valve.The automatic pool cleaner itself should have all the hoses disconnected and stored laid out flat if it's a suction based cleaner. Don't coil it up or you'll be buying new hose in the spring. If it's a Barracuda or Kreepy Krauly, take off the pleat, on the unit, rinse it and store it flat.
For most pools, that's it on the suction side of things.
6/ Return lines. Hook your blower up to the opening where your salt cell was. You'll be blowing backwards, through a heater (if you have one) and through the top of the filter out through the pump. Make sure those suction lines are closed or you may blow water back down those lines you just winterized. Keep the blower and yourself clear of those drain cocks in the heater header as well as you feet away from the base of the pump or you'll get a soaker. Make sure the filter is on "recirc". Turn on the blower. When you see only slight spits from the heater drain cocks and from the pump drains, you're good. Close the heater drain cocks. Add antifreeze to the line and blow. You'll see antifreeze make it's way out of the pump drains. When you do, you're done. Your heater and filter top are protected. Put the filter on to the winterize setting and remove your pressure guages.
You'll need to switch the position you're blowing into. Put the blower hose into the other end of the opening for the salt cell that leads directly to the pool. If you have a slide (remove the hose at the slide) or waterfall, start with either first and close the pool return valve. Blow until you see little or no water and follow up with antifreeze. Generally, there are no winterizing plugs to install here for either.
For your pool returns, close off any other return valves (waterfall or slide) and turn on your blower. Starting with the return that's closest to the equipment, you'll be plugging off the returns in sequence, temporarily. The retun closest to the equipment is almost always the one that rids itself of water first. Just go to it and when little or no more water comes out, only air, temporarily put a winterizing plug in there finger tight. Water will now come out the next nearest return. If you have more than two returns then termporarily plug this return off to force water out the next one. When all returns are blown, remove your plugs and load the line with antifreeze. Turn on your blower and race the antifreeze to the pool. :)
Where you see it come out, plug. Repeat until all lines show antifreeze coming out. If you have a buddy seat with jets, include that in comments and I can tell you how to blow that out, otherwise I'll just leave it at this.
7/ Cover time.
Put in your winterizing chemical kit.
If you have a waterbag cover, fill the bags half full, no more. Lay out the tarp on top of the pool and adjust it so that there is at least 1 foot of cover on the deck and the cover goes straight down the wall then goes at a right angle where the pool water surface meets the wall. There should be no cove there at all. A proper fitting cover can't have any tight spots that will eventually pull in over the winter with snow load.
If you have a lock in cover. These are a breeze, you just need to figure out where your corners go as these types of cover are usually customized. A helpful hint with these covers is to fold the edges in to make a "boat" and you can put it on the pool surface without it sinking, making it easy to rotate around to find it's best fit. Insert the bead of the cover into the top track of the coping, making sure it goes in properly. When it's all on and looks good, use liner lock at corners and every few feet along staight runs to keep it in place.
If this is a security cover (trampoline type) and it's you first year with it, you're best to get a pro in to do it, especially if the anchors haven't been set in the deck. If the anchors are there and the cover straps have already been adjusted for them then by all means, go ahead. Bring the anchors up out of the deck around the pool. Most cover manufacturers use the same type of anchor and a wrist saving tip here is to use a corless drill set on reverse and any screw driver tip inserted backwards with just the hex base out will do the job. It actually fits perfectly and takes a 30 minute job down to mere minutes. Start at the steps, as that's the easiest to figure out what strap goes to what anchor and you won't go wrong later in the strapping process.