i keep track of everything
-feeding or refusals
-urates/urination
-defecation
-any unusual behavior (i have a little spot on my charts i can write in stuff)
-weight

etc

i just do it because they do everything so infrequently you can forget when the last time you fed was or something. i have everything infront of me with my charts so i can see, at a glance who isn't eating, who was just moved out of quarantine, who peed recently, etc. unlike my cats who need stuff done every day.

it also makes it easy if i have someone come over to watch/check on my snakes when im gone so i know what happened while i was away.