It started by letting them get out on their own.
If they could get down on the stools, then they could get back.
Knowing a treat was waiting sure helps. I guess that's what got them doing it in the first place.
Once I has so many, 20+ I had to start using a timer, or I'd get carried away with one run and the last bunch would end up with short runs.
They soon learned what the timer meant.
Most just followed and learned from the rest, but some I have to physically catch them and place them from stool too stool saying up up. After a while most will know what to do as soon as I say up, then as soon as the timer goes off.
The kits and a few who don't yet will run too the tapping of the bath bottle.
It was all an attempt to keep the stress of catching them down.
Some runs/play time are of 4 or 5 chins, and they would all run in different directions making catching them and putting them back stressfull for all of us.