My mate put his bike upside down and it ****ed up his fox forks. Something to do with wee bits of plastic swarth blocking valves.

I'd hang them up if you can in their normal orientation, stick plenty of grease/lube on things prone to corrosion/that you want to protect like fork stanchions, mech pivots, spd springs, chain etc...

If it was me, I'd do a fork lower service on my return.

Maybe take the brake pads out & store them somewhere dry if your shed/garage/cellar is damp.

Probably all a bit over-cautious, but it's what I'd do.

i'd get a mate to look after them 🙂 they need ridden at least once a week

its a bike in a shed/garage not gonna come to much harm, clean it, lube it, leave it!!!

If you're really paranoid get someone to jump up and down on the shocks every now and then.

(respect for going where you're going) 🙂 Rich

I'd not do anything special, my nice bike usually gets the winter on it's lonesome in the shed.

Give it a thorough service before you go, then it's ready to immediately jump on and hit the trails when you're back.