Here are a few ideas to get you started: My spouse's paperwork has helped us change habits around the home to better fit their needs. They're getting better at self-advocacy, in part because it's easier to articulate what exactly feels wrong. Their quality of life was directly improved because we read the paperwork together, and took action based on it.
This is something you can do with a self-diagnosis. If reading the literature on autism gives you processes that improve your life, you don't need the diagnosis to confirm that. The life improvements were the end-goal in the first place.
This kind of presupposes that you have suspicions about autism rather than just something in general. If you think you have autism, you're can target that literature anyway regardless of the diagnosis, while if you have no concrete suspicions, you'll be firing blind, and probably miss a lot more than if you could nail it down to one diagnosis.
By the time I got mine, I didn't need the processes, since I'd figured those out by myself, so the diagnosis is just a nice piece of paper pointing to a road I've already walked.
For ADHD though, that story is very different, since step zero there really should be medication,[1][2] and that is locked behind a diagnosis.
