Here's what my kneeboard page looks like. And yes, I save all of those.
On the top, it's the date and tail number.
On the right, start, tank change, and stop times, in case I want to know how much gas remains (unless there's a leak, obviously). In case of a rental, there may be tach and Hobbs times recorded.
"Canopy N118MM" refers to a Mayday call that I heard, a glider lost canopy and was landing out. There's an approximate location and time.
On the left, I may have airport diagrams, sometimes with marks about non-standard patterns and the like.
For example GUP's TPA is 7400 ft.
Weather at CDC was 200@8 30.00 and no significant clouds.
In the middle, I mark the identity of the ATC facility, and in this case I took something for LA Center, which turned out to be SL Center when I got to it. Obviously there's also the current altimeter and frequency.
For the RNO weather, the underscored S means the ATIS Sierra. If ATIS includes something noteworthy like runway closures, it may be marked there too.
On the very bottom, stars designate squacks, such as "Baggage door support strut broke" and "No 1090ES TX" (which fixed itself).
A while ago I was fascinated with the idea of replacing the kneeboard with something electronic, but I procrastinated long enough to find out that tablets cannot be trusted. One time my daughter managed to factory-reset my main navigation tablet, wiping out all the data on it. I ended making a precautionary landing and using an airport WiFi to restore it. Good thing we weren't crossing Gulf of Mexico at the time.