Left and right are not correct. A sideways tilt of the head while maintaining eye contact means “follow me”, a sideways tilt of the head with a glance in that direction means “look over there.”
The beard looks fake and it’s weirding me out.
Also, as an autistic person, you’re missing a gesture. It’s to stop moving and stare in horror like a deer in the headlights, because you’re unsure what’s happening or how to respond.
Why is this so accurate?
It’s not.
“Hey, look at that girl/car/tree/Chihuahua” isn’t a left nod. It’s eye contact, then you look at the thing.
“Come here/go there, let’s talk” isn’t a right nod. It’s a weird neck movement where your head is kind of sideways and you’re nodding in the direction of the place you want them to go. You usually use “Hey, look at that tree” first before you try to get them to go to the tree to talk.
Can confirm up and down are correct enough, though. Up is for people you know, down is for people you don’t.
A man’s up nod is for a stranger: “I will not try to kill you if you don’t try to kill me.”