To do anything more than simple additions and substractions, I found I needed the following information:

* date,

* amount (+/-),

* beneficiary,

* account (N° or establishment),

* a short memo (can help with cross-category expenses, such as moving: requires gas, train tickets, movers, new furniture, selling old furniture),

* and a (sub)category (gas/car, train/trips, "Livret A"/saving, etc.).