Hello,
For my photos files I describe the Greek coins by city first, Roman coins by ruler first, Roman Provincials by city first. After that is the weight, width, reference (with mint name for Roman), when and from whom I bought it. But photo programs have a limit to the number of letters I can use, I think it's around 130. All the photos are alphabetical A to Z. I think about 60% of the photos are my own. I keep the photos on my cell phone and on backup drives in case my computer crashes. Someday when the collection is sold I or my daughter can send the photos in a flash drive to dealers for consideration to buy or sell on consignment.
This works for me but others may have something better for themselves. Many auction sales list Greek coins geographically from west to east and Roman coins chronologically by ruler. But one would need to use a number first in each photo to keep them ordered this way.
I also keep a document file of my collection, number 1 through.....in the order I bought them. Each coin has a brief one line description with the cost. At the end is the total cost so I know how much I've spent over the years. My wife sometimes comments it's too much!