I do rotation play as well. I don't keep tracks of seasons, days of the week, or anything but a strict, 15-day "cycle" per household. Each cycle starts at nearly the age up hour and ends at about the same hour, but on the next day of the week. For example, a Burb household starts at Friday, it will be played until the 2 next Fridays are passed, and ending on Saturday 17:09.

I usually keep to one household until its cycle is over. Counting day and night number helps with keeping track. I pay little heed to the order of events or what each household does, so long as it is played till its time is filled.

I don't use spreadsheet, and don't want to use the Story Progression mod for I am a control freak, and instead sort through my neighborhood backups.