I' ve kept one for the last three years. Keep track of the following: day, time of hunt, temp, wind direction and mph, attire and equipment, location of hunt and stand, activity. This is on every entry, but some other things I keep track of through the year: scouting, harvest times and what my buddies have been seeing as well. It' s pretty neat (and valuable) to check back over the last year or two to see the activity, temp, etc. I definitely recommend keeping one.