To lock my scooter, I’ll thread a cable lock through one of the suspension arms and around whatever I’m locking it to. I also install a lock on one of the disk brake rotors (see pic). That way, even if someone were to cut the cable lock, they’d have to pick up a 110 lb scooter and carry it away because the brake lock won’t allow it to roll. Most of the time I’ll also fold the steering stem down where it will lock in place. So unless a potential thief knows how to unlock the stem to unfold it, the scooter will be sitting on the floor. If the scooter will be in my line of sight I won’t bother using the cable lock and just fold the stem and use the brake lock.
I posted an Amazon link to a disk brake lock with a movement alarm. They are also available with Bluetooth, though the limited range makes that pretty useless unless you’re going to be fairly close by. Most of these locks come with a coiled cable. One end is attached to the lock itself and the other end is hooked to one end of the handle bar or to one of the brake levers. It’s purpose is to remind you that the lock is there so you don’t try to ride off with the lock in place. Needless to say, that would be really bad.