Every time I report for a trip I get a printout (flight numbers, cities, scheduled flighttimes, etc.) and as I fly the trip I scribble tail numbers and landings on that sheet.

Like UnlimitedAkro, I also make a second set of printouts at the end of the month that will have the actual flighttimes on it.

I sit down every couple months and use the first printout for all the boxes except the actual block time, which I get from the second printout.

The only catch is not losing the half-dozen sheets you've collected during the month. Find what works for you and you're all set.

Presto, no empty boxes.