I’m autistic, I’ve had one haircut since covid because I hate the sensory aspect of haircuts. I’ve been searching online of how to cut hair and it doesn’t look that hard, but a lot of people seem to advise against it. I think that if I fuck it up it’s not the end of the world, I can just go to a professional. But I have very long hair so I have a lot of opportunity for trial and error. I think that if I get some practice, it’s something I can continue to do going forward. I also don’t particularly care how it looks, I just want it to be shorter.
Also autistic and did this for a few years. For a basic dude-cut, you can use buzz everything however short you want, then every few weeks after buzz the sides and back but let the top grow until it looks like it’s time to buzz your whole head again or you decide to let it keep growing back out for a bit. Pretty easy and low maintenance. Takes practice and follow the other person’s advice to shower and go back over your head to make sure you get everything, it’s harder than it seems like it should be. And you’ll need someone to help get your neckline at some point.
This cut might start out a lot shorter than you had in mind when you asked the question, or maybe not. When it comes to wielding scissors, that’s not something I can really attack my hair with, so I don’t have ideas that would be helpful in that regard.