hitting them with the earthquake and then closing the game and going away. Then a couple hours later I would open up, hit them with the earthquake, and close up again.
Check on the fire while you're there. There are 90 people around and as long as a bunch of them are farming, and some of them are checked for parenting, the village will be fine. I also had several on devotion to make sure that my earthquake is ready when I come back, but this might not be necessary.