I have three with one on the way. It’s a constant struggle to keep the place livable. Before I had children I was not a neat person and kept things livable by not doing things that made mess and staying out as much as possible. Can’t do that with kids, so what’s the trick?
The only way we’ve kept our place livable is to get the kids to clean at an early age. If they can get a toy out, they can put it back. We started out doing most of it alongside them and giving lots of praise for every toy they move in the right direction. Then half of it alongside them while encouraging them. Now we have little helpers who will put piles of books and toys away to watch a movie, and routines of clearing the living room floor before dinner. Things aren’t spotless, their play room is more piles of sorted toys than really clean and cleared, but the place is livable.
This is totally it, making sure your kids know how to clean up is #1, and then tying the work to positive reinforcement, eg “You can play video games after all the Legos are picked up,” or “We can watch TV after you put away your laundry.” The key is consistency and follow through. If you don’t follow through, your kids aren’t going to either.
Also key is applying these rules dispassionately. No matter how your kids emotionally react to a rule imposition, you remain calm. If you react with anger, frustration, or irritation, you risk throwing everything off course