So: get up in the morning, shower, dress, breakfast. Commute to work, work throughout the morning, take some time for lunch, back to work until the end of the evening. Commute home, have dinner, attend to duties of household and family, engage in some sort of minor recreation activity before settling down for (preferably) eight hours of sleep to repeat the following morning.
An average day for the average person in modern day North America.
But if you expand it to all the humans on Earth, then it's a different story. Different rhythms, different daily rituals. Although most humans prefer to operate in the daytime and sleep at night, even that is hardly universal.
So, of course, for alien species, the "daily" rhythm is going to be something quite different. Even what might be considered a "day" to them could be very different, depending on their biological needs and the rotation of their homeworld.
I started thinking about this more and more with Banshee. As with many things in that work, I thought about something that was sort of taken for granted on Star Trek, and inverted it. Namely, the way the time schedules work. Sure, they use "star dates", so it isn't just exclusively using the Gregorian Calendar, but the day-to-day is still very human. Life on the Enterprise or Voyager is still a 24-hour day*, and the duty roster is split into three eight-hour shifts. There's still a "night" shift**, which is incredibly arbitrary in space. It's not like things are quieter or less active because of when you decided to schedule your sleeptime.
But what's fascinating is, at least on Trek, there isn't even much lip-service to the idea that Klingons, Vulcans, Trill or any other species might be on a different life-cycle. One exception: Phlox on Enterprise, whose need for sleep is essentially a six-day hibernation every year.
Now, part of the fun I've had on Banshee involved taking that to an extreme: you have a ship with eleven different species, and each species is on a different rhythm. To the point that the higher-ups don't even bother setting a schedule or "ship's time". You need to sleep, eat, or deal with other biological functions? Go ahead. That's your priority, and you deal with it as you need. It's not for anyone else to say you can't do that.
For a human officer, used to a strict regiment and set duty roster... that's very disconcerting. But that's part of what she needs to learn to deal with.
*- On Deep Space Nine, they at least had a 26-hour day, which was based on Bajor, but even still: hours. And the rest still applies.
**- "Night" shift might be on some universal-ship time throughout Starfleet, but it seems to be more, "When the Captain is sleeping, that's the night shift".