Wanted: How to set up a Gemini server, for complete idiots.

I've never sys-admined or ran a public-facing server -- well, not in the last 30 years, anyway. So I have a healthy fear of forgetting to do something obvious and getting pawned immediately by some script-kiddie. Beyond my router, monsters roam, waiting for a crack in the fence.

I also have a few Raspberry Pi's sitting around.

Perhaps someone could put together a simple guide for setting up a Gemini server. Really simply, no frills, self-signed certificate, no third parties involved. All the steps in setting up a reasonable level of security.

I am sure I am not the only one who needs guidance.