Some bike storage spots require empty fuel tanks. For drained tanks I put mothballs in to prevent rust - whatever moth killing gas they produce drives out the air (no oxygen = no rust).
DEFINITELY drain the carb bowls and disconnect the fuel line(s) at the petcock. The fuel will evaporate at least partly: worst case it will dry out to a nasty goo that corrodes the carb metal, best case it will be total crap gas and the bike will be a bastard to start in spring unless you drain them then anyway.
If you use gasahol (ie real gasoline is not available where you are) then drain the tank as well even if in the bike is stored in your own shed or outside. No-ethanol gas will be OK over the winter, tank should be as full as is practical. Adding fuel stabilizer will be good. Draining this fuel -get fresh bike gas and mix in the "old" stuff into your car or whatever in the spring- is a good plan.
Adding methanol "gas line antifreeze" is good, it absorbs water into solution with the fuel that would otherwise puddle under the fuel and cause rust. The ~10% ethanol in gasahol will do that as well, but unfortunately ethanol doesn't absorb much water before it drops out of solution and you get a puddle of ethanol and water under the fuel also causing rust. If the tank is almost 100% full you won't have much any water getting in anyway, temperature changes expand/contract the air to blow/suck it in and out and the water is from the new air... less air in the tank = less breathing = less water in the fuel.
Oil... depends. If it has a lot of miles on it, I change it soon before storage and get a bit of riding in so it's circulated fully: dirty oil can be somewhat corrosive plus the soot and whatever in it will settle into a layer on the bottom of the sump/tank and just mix right back in with your new oil in the spring. If you have relatively fresh oil that looks clean - leave it over the winter and change it in the spring or just ride until it's due to change. Oil won't "go bad" in a few months sitting in the engine or tank.
Fogging oil is not so easy to use with 4 carbs especially wit the brutal intake plumbing. Pop out the plugs, shoot a CC or two of 2-stroke oil into each hole (a pump oilcan is nice for this), screw the plugs in all the way but not at all tight and crank the engine for a few seconds.
Spray the chrome with WD40 - forks, wheels, fenders, bars, pipes, etc. to avoid rust specks or worse. Cover the bike with a dust cover, old bedsheet works well. Don't use plastic, that keeps moisture in... and rust never sleeps.
Outside storage - not the best obviously but you gotta do what you gotta do: really lay on the WD40 on chrome. Spray a mess of it into the exhaust outlet then plug it - plastic bag and rubber band works nicely. Cover the bike with a waterproof but breathable cover. You can cover it with plastic sheet but leave plenty of ventilation - don't try to wrap it around the bottom and seal it up. Watch out for friction wear: tape some cloth or plastic foam over parts that the cover touches - wind will be whipping your cover around, and I've seen side covers and tanks with the paint worn through in spots after a winter under a cover.
Rodents: Mice, rats, voles, shrews... like to get out of the weather inside garages and sheds, and they love to chew on plastic and rubber. A mouse can get through a 1/4" crack under a door. Grass seed, bird seed, anything edible in the space... irresistable invitations for these little buggers to drop by and stay until it's all eaten up... and they'll be gnawing on anything suitable whenever not eating or breeding. Put mouse food elsewhere. Put some poison and/or traps around. It is not a fun spring day when you find the insulation gone from your wiring harness.
Battery - lots of theories for these. (I use old-fashioned lead-acid ones: for other types do what's recommended for them, I don't know) Stored inside I leave it connected to the bike, with a battery tender on it for a day every few weeks. I check fluid level in the spring, and always have to add a bit o'distilled. If the bike is stored outside you should bring the battery inside (good idea anywhere but in really cold places it could freeze and burst - you don't want battery acid dribbling down onto whatever it will ruin) check fluid level and add pure H2O if needed. Either leave it undisturbed somewhere cool and dry, or charge it once or twice over the winter. Check and top up the electrolyte level in spring. Check level before and after a spring charge.
