@icebunny08
I play rotationally a lot!
So, the first thing I do is set aging to active household only (or off) so the other household isn't growing old while I'm playing.
I usually switch houses between midnight and 2am on Sunday (later if the household contains someone who works in Mixology or Special Ops, because they get off work at 2! If you have someone in the Criminal career they work nights and you might have to adjust your schedule). That way I have a full week of work/school and don't pop into the house while someone's missing something they're supposed to be at, because the game doesn't send your other households to work or school, but if they miss work or school they get lowered performance (if you're playing them). (In other words: If you pop in at 1am and your Special Ops Sim or Mixologist works until 2am, they missed work and have lost performance for skipping work.) Basically: Some time when they're not supposed to already be at work or school. Since this is the middle of the night, inevitably they're all awake playing on the computer and need to pee and eat. LOL. My first agenda is to manage needs and, as I phrase it, "put my idiots in bed." 😉 I want them on a schedule for work/school on Monday! On Sunday, any children or teens do their homework for Monday. 😉
While they sleep, I look at career/aspiration/character values/etc. to reacquaint myself with where we were with this household. This might be redundant if you have two households, but I have a save with 8 or 9 families I play regularly and another I pop into to age up the potential friends/love interests I created. (Sometimes I cheat with "barely played" households and use something like Life Decider or MC Cheats to randomize their skills.)
I have two rotational saves where I play everyone equally and one where I play favorites. It's all up to you and how you want to play it. I still recommend a Sim week as a good amount of time to spend with a family, minimum.
If you send a Sim to University, you're committing to play them for three Sim weeks. Sadly, you can't enroll them and expect them to do their schoolwork while you're playing another household. There's a bug report about it, but honestly I think that's a function of how rotational play works. Your Sims don't get promoted, gain skills, etc., while you're not playing them. They don't earn money or royalties, or accumulate bills. They do not do their homework.
If you use mods, I HIGHLY recommend LittleMsSam's automatic thermostat. Otherwise, when you pop in on Sunday at 2am they'll all be complaining about it being sweltering or morgue-like in the house because the thermostat is how you left it last time you played.
Oh, and if it's a holiday? Switch houses after 2am or else you'll be treated to whining about how Love Day was AWFUL and they're all SO SAD. They do not fulfill holiday objectives without you.
All that said, I really enjoy playing like that. One week you're a lesbian chef married to a writer with an adopted daughter, and the next week you're a scientist with a wife, a son, and an alien daughter, and the next you're a musician or a businesswoman or an astronaut or a doctor or a stay-at-home mom. There's no time to get bored with one particular family or career.
Some people keep paper notes about where they were, but I like winging it. 😉 It might help with job schedules, though. Just make a mental (or paper) note of when on Sunday it's safe to pop in. I just remember the exceptions to 1am on Sunday.