At the October 2019, Strait Macintosh User Group had a brief demonstration of how to securely configure macOS Catalina. However, as the meeting was only an hour long, and there were lots of questions, most of those in attendance emerged dazed and confused. This included the person giving the presentation, but Lawrence Charters promised to publish a guide to the major points covered. He implied it would be published soon. He was wrong.
But the configuration document is now complete, and can be found at this link: