What do you use to winterize?

I make little pouches of diatomaceous earth and pour lemon oil or lemongrass oil on it and toss in the cars for the mice. The ones inside the barn, I crack the doors and hood and boot so as not to squish the weatherstripping. Make sure the antifreeze is good for the temp. I don’t use ethanol gas, but if I did, I would probably plug the fuel line and run the carb out of fuel