well I have a rather elaborate process for washing my car in the garage w/no drain.
My apartment home is 125 feet from the garages. I have two 25 gallon water tanks that I move between the house and garage with a hand truck (I run a hose from one of the washing machine spigot's out the window to fill up the tanks with hot water).
I have a cheessy craftsman water pump that pulls the water out of the tank and into my DI System then out to my pressure washer (electric). I bring two buckets of water (one wash one for rinsing the mitts) with me when I come out, along w/MF's and WW's)
I put up painters plastic on the side walls cause they're unfinished (drywall) and left it.
As for the drain bit. All garages should be "pitched" to the rear so water drains out. Mine is pitched to the rear and to one side. I made a small barrier on that side so the water goes out the door and doesn't pool up in the corner.
Well this all may sound extreme but let me tell you, I tired the QEW thing and while I did like it, could not bring myself to just drop a wet mitt on a really dirty car, esp in the winter, so I was running to the coin-op to use their Pressure wand to hose the car down, but it would be no better by the time I drove 1/2 to get home.
And while we do have somewhat decent laser washes up here, when there was a break in the snowing (not often but it happens) the lines were around the block and they bays would be filthy with dirty snow up to the top of my snow boots. Esp from people running thier pick-up's with snow plows on them through despite signs saying not to do so.
Nope, I wash my car no differently in the winter than I do in the spring and summer, nice and toasty warm, and stick to the same regiment that keeps my Black Audi looking sharp.
You have to get creative sometimes when the resources aren't readily available.