We have a big filing cabinet, with everything in clearly labelled hanging folders, arranged in alphabetical order. I just don't know how anyone manages to keep track of everything without some kind of order! However when I first met my husband, he just had a spike and everything got stuck on the spike, it meant he knew where all his papers were but they were in a random jumble with a big hole in them from the spike, if he needed to check any details!
When my mother-in-law died, we had to turn her house upside down to find her Will and in the end it was in a drawer with her tablecloths. So we impressed on my father-in-law that he needed to be a bit more orderly, so all his papers were in a briefcase when he died. They need a bit of sorting but at least they are all in the one place!