My husband and I are almost 40 and both ADHD. Here’s my advise from years of struggles:
1- get a house cleaner: I know it may be an expense that you think you can’t afford but it by far has been the best decision we ever made. We both sucked at cleaning and were not organized. Knowing she is coming everything other week and knowing the house has to be organized ( somewhat ) is a great motivator. Coming home to a beautiful, clean environment helps you complete other tasks that are needed around the house. Having friends over when your house is clean is a perk.
2- make organizing fun: I go on Pinterest for ideas, take one place at a time and try to figure the best way to organize it or sometimes just do it and see how it works. I watch tv when I’m sorting things and finding places for them. It gives me something to do when I watch tv bc I have to be doing something. I teach my husband and daughter where things go and sometimes they don’t get it but I can fix it bc it’s not too overwhelming when it’s not everything. It becomes a habit after you’ve been doing it so long. My husband has his things( his fishing gear and the garage) that he likes to organize too. My 3 yr old daughter likes to put things in containers (little ones I buy at the dollar store- which is a great place to get stuff for organizing) and she’s learning a skill earlier than we did and with us as parents- sheesh, she’ll need some skills!
I still have lots of things to organize and make more efficient or work better( things jammed in drawers or closets) but I do it when I have time and I make it fun!
I do have a hard time throwing things away sometimes so I think of how I can reuse them or upcycle them.
Anyway I hope that helps in some way- it’s just been our path through trial and error. You’ll find yours✊