Make a plan that you can do in 90 minutes, where the outcome will be better than the starting position.
Next time, make another 90-minute plan.
Maybe this will be less effective in total, e.g. you might need three or four 90-minute sessions to accomplish what you could do in a single 180-minute session. But if the 180-minute session is unavailable, this is the best option you have.
For example: Instead of vacuuming the whole house, do one room at a time. Instead of putting all things to their places, on day 1 collect all things and put them into a temporary basket, and on day 2 take a few random things from the basket and put them where they belong.
Ah, okay, this helps a lot.
The issue is that, normally, there is a sharp transition from "enough clutter to feel messy and be hard to find things" to "clean enough that I can find things and it doesn't feel cluttered". This transition is in the last 30 minutes or so of the 3 hours. This means that:
on day 1 collect all things and put them into a temporary basket, and on day 2 take a few random things from the basket and put them where they belong.
will help solve the first half of the problem (feeling cluttered), even though it won't ...
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
To any future monthly posters of SQ threads, please remember to add the "stupid_questions" tag.