April 2021: Good news everyone, see the updated post.
Raspberry Pi released a new Raspberry Pi Imager tools for easily flashing image files to SD cards. While the info-beamer installation is already incredibly simple, the new tools is quite shiny and since yesterday, info-beamer OS can also be installed using it. Get the tool, then start it like this:
rpi-imager --repo https://info-beamer.com/repo.json
You’ll be greated by the main menu:
Clicking on CHOOSE OS allows you to select the version to flash:
After that you can select and SD card and click on WRITE to flash the image to an SD card. Maybe there’s a way to get info-beamer to be included directly within the official OS selection. I’ve opened up an github issue about this.