I am a new hobbiest beek with about a dozen hives just finishing my second season. I must fit my beekeeping efforts around my full time job and a few other activities.
The first year I had 4 hives, and I could just remember everything I needed to about each hive. The second year I went to 12 hives, and my memory was no longer good enough so I had to go to record keeping.
IMHO, the key to keeping records is finding the right balance between information retention and the amount of time the keeping records consumes. In other words, if the record keeping process is too cumbersome because the recording method is awkward or the amount of data entered is too voluminous, you won't consistently do it and the records then become useless.
I first tried a notebook, but it added way too much time to the inspection process. I thought about some electronic method, but messing with a smart phone or recorder during inspections also seemed like too much work. Also, Sitting down after inspecting 12 hives to convert the electronic records to something useful like a notebook was just too much.
I finally settled on writing notes on each hive's metal hive top with a Sharpie pen. This method is super easy, the record is automatically correlated with the correct hive, and all the info is right there in front of my face just as I open the hive. When I run out of room, I erase the first entries and keep going. Info like queen and honey produced is preserved on the top line and changed as needed. This provides about a 2 month rolling hive record. For me for this year, the Sharpie pen on the hive top has worked really well.