My negatives are in Printfile sleeves, stored in a 4 ring binder. Nothing is written on negatives or sleeves. All negatives are scanned, and a contact sheet equivalent of each page printed to be filed with the negatives. This contains the negative numbers, running consecutively up from 0001 with the binder number (and type) as a prefix. e.g. LF010023 would be the 23rd negative in large format binder 01.
These contact strips can be viewed on my computer to enable reasonably fast access to a negative. Except that when the number of sheets exceeded 100...