When I first started reloading shot shells,(35 or more years ago) and was loading four gauges (OK not many 410's) and seven shot sizes, I had to come up with some way to distinquish loads. I assigned a different color to each shot size: black for 4's, yellow for 5s, blue for 6's etc. I would then take the tray of primers and spray them the appropriate color for the size shot I was about to load. A couple of light sprays with time to try in between was all it took. When I pick up a shell, years or decades after it was loaded, I still know what it contains and a quick breech of your double and they are looking you in the face.
