latest docfx version needs to be installed. This can be installed via chocolatey
To pull in the latest source of a project you have to navigate into the ext folder and checkout the required revision (by default these should always be pointing to the latest tagged full release)
run build.cmd/build.ps1 from the command line. This will checkout that latest tagged commits for each of the repositories and regenerates the site in the docs folder.
run serve.cmd/serve.ps1 this rebuilds the site but also runs a dev server at http://localhost:8080 so you can preview the current state of the docs.
To make changes make sure you rebuild (run build.cmd) before committing. TODO: automate this as a build step.