In front of my room, ground floor. I have master locks for both front brake rotors. The ignition is locked and the forks are locked. Most important, a bright orange cord from the left clutch to the right brake lever. I also have a generic cover that does NOT advertise HD!
I use the alarm and locks that came with it and a small disc lock. Small, portable and tough as hell to break. Nothing fancy but locks and alarms keep honest people honest. If someone really wants to steal your scoot, you can't eyeball it 24/7.
Insurance.
The rest of the suggestions are just "feel good" options.
They ain't gonna keep me (well, not me really) from stealing your bike if I want it.......