On the exposed roll I mark in short the subject, the date, the consecutive number if I used more than one roll that day, and, if needed, a hint for the developing if the ambient light is delicate (shadows<—>highlights) or, eventually, if the exposure deviates from the box speed.
But on the pergamyne negative sheets, there I mark as much as and whatever I think is important, technically as wel as subject related.
And I stick Post-It notes with printing instructions for when I need to re-print that negative.
The sheets are classified per datum in boxes containing about 80 to 100 sheets which on their turn are arranged per year.
I keep 2 paralel spread sheets describing the contents of these boxes, one per datum and one per thema, and are systematically updated.
I make the boxes myself.
The same goes for the prints.
I don't make contact sheets as I find it somewhat a waste of material and time, and I am used to 'reed' the negative on the light table...