This is the workflow I use for anvil apps where I want multiple copies of the app for development and testing purposes or where I want to collaborate with somebody else on its development.
For the purposes of this guide, I'll assume there is an existing app at anvil called 'my-app.' That's already live and it will become the 'production' copy.
Any other copies of the app are for development purposes. They can be created and destroyed as necessary. Their history is not important and can be overwritten.