I took a time management course that someone with ADHD developed, and the best advice in it was that "Everything has a home". Part of the initial process was finding homes for things and then designing an ongoing temporary home for future things that need sorting out. In my case, I got a wooden inbox. I put receipts, mail, papers, etc., in the inbox and then regularly sort it. If it takes a few seconds to resolve (this is a receipt; toss it or file it), I do that.