cant see why you'd want to coat the spark plugs in anti seize graphite grease or copper grease

Another one would be check theres enough antifreeze in the coolant system, cracked blocks are not good come summer time!

generally make sure you keep it clean before you store it, leaving cars dirty isnt good for the paintwork, though they will take some grief!

also with outdoor storage and winter driving, if you have some nice paintwork, i usually keep it waxed, especially the bottom half, stops rains and dirt gathering so easily... this is the same for driving it with grit on the road... check your coolant, and generally keep it running often,

another top tip, on cold mornings, dont give your car death over speed bumps, much more likely to snap a spring in cold weather...

and simple but true, take all valubles out of your car... I'm amazed how many people still leave valubles on display!

loved the tip about salt or cat litter, makes sense! hate musty cars lol