The less you have, then the less you have to manage, clean, and work around. Many ADHD experts recommend having as little stuff as possible. Then you can see what you do have and function better.
Given your current state of overwhelm with it, you might consider hiring a professional organizer to come in and help you get to the point where you can easily maintain. Ultimately, you need a system that works for you, not necessarily the way others organize.
ADDitude Community Moderator, Parenting ADHD Coach, Podcaster & Author, Mom to teen w/ ADHD, LDs, and autism