The "before" picture.
This folder alone is just chock-full of random receipts.
What I needed: manila file folders and a pen.
First I emptied the whole thing out and sorted through the mess.
Most of the documents in my filer could be destroyed: a lot were old receipts that weren't important. I also had a lot of non-financial (or otherwise important) information in there, which I sorted to and relocated to more appropriate places throughout our home.
You can create file folders for whatever categories make the most sense to you. The articles I read recommended creating an "action" folder for things you need to work on immediately, but I generally don't put things in my filer until they are completed, so I didn't do that. Instead, I made folders for Taxes (for every year I've filed), Health Insurance, Insurance through State Farm, Other Insurance (life insurance through my employer), Retirement folders for both our IRAs and my pension, Warranties, and two folders for my receipts: Banking (Current Month) and Banking (Prior Month). That way I can just throw out the whole month's worth of receipts at a time, and start fresh each month. Once you have reconciled receipts to your checking account, you don't need them any more except for warranty purposes, or if you itemize on your taxes.