Get a local copy of this repository, set up a Python3.6+ environment and run:
pip install mkdocs mkdocs-material mkdocs-minify-pluginCreate a branch, make your changes, commit and make a pull request.
You will see results by running python -m mkdocs serve from the top-level directory. The website will reload upon file changes.
Go to the current version of the site here and click the page's modification link.
See the Mkdocs documentation for more.
See the Material Mkdocs Theme documentation to understand the settings and plugins.