I'm writing this as I take a break from trying to capture back a part of my house that had been lost to the mess, so let's say I'm in progress on that front.

Try to think of it like refactoring spaghetti code. One function (room or in my current case a single closet) at a time or it will be too much. When you do part, do it right. Make homes for things and only put things in their homes. A tiny area that is nice will give you more positive feedback to keep on than an entire house that is all only 10% better.

Also like the spaghetti code, you got into this mess because you were rushed before. Unless you fix that sense of rush and chaos in your everyday life, things will fall apart again. How chaotic my life feels creates mess which makes my life feel chaotic in a negative feedback loop.