what needs to be done to your bike before you put it up for the winter. if it is going to sit in the garage for 3 months.

 

I've heard to change the oil, though I've never done it.

Fill it up
fuel stabilizer
cover the exhaust/intake(you don't want any mice going in there ha)
wash it(you don't want salt on your bike all winter)
cover the bike

Not in that order lol

 

All the above +

Center Stand .......tires off the floor.......check coolant against freezing

Pull the battery store in above freezing storage put on a battery tender
at least once a month

 

If it's a carbureted bike, you may want to consider draining out the carb bowls, too. (if it's gonna sit for a while). A full tank of treated fuel is definitely important.
And a battery tender is important, too.

 

Add stabile, fill tank as full as possible, change oil, remove battery, cover and wait till next year.... keep the battery in a warm dry place and trickle charge every month or so.

 

This might be OT:
I never thought having a motorcycle had this "hybernating" season.
My motorcycle never experienced one.