ADHD = Stuff everywhere around the house, no rhyme or reason, sheer chaos.
Autism = Stuff neatly organized.
Autism + ADHD = Neatly organized stuff all over the house in random, inexplicable places.
My planning and organization isn't the best, usually, unless it's with my guitars and guitar gear, then it's quite meticulous. That said, when organizing for ADHD, I find point of performance is helpful, and for autism, the phrase "A place for everything and everything in its place," is the motto to go by.
When you have both, the default is the DOOM method.
DOOM means Didn't Organize Only Moved.
I find getting a control on DOOM piles is the hardest thing. So, I designate a place for things where I didn't organize, only moved them. Like, for example, the laundry chair is for when clothes are too clean for the dirty laundry, but too dirty to be put away with the clean clothes.
Clean, in the sense that everything has a very specific spot where it stays always. If anyone moves one of my items it makes me very upset bc now it's not in its spot. The only time my space is really messy is if I get something new that I don't have a place for, because wherever I happen to put it down I'll just leave it for weeks. That's also how I lose things, if I don't have a place I know it'll be I'll never find it lol.
I like things being clean and tidy in my home. Sometimes if I get super busy I can let things fall into slight disarray but I'll always end up organizing things back into their place before it gets out of hand.