First, you need to get a browser with WebGL, as well as a copy of node.js and git. Once you have all of that set up, you can install the workshop using npm, which is included with node:
The script will ask you if you want to create an answer directory, press y to accept. This will populate your current directory with shader files for you to edit for each lesson – hopefully, it should also automatically open your web browser but if it doesn't you can find the workshop menu on http://localhost:12492/.
Feedback and criticism is welcome, please log your troubles in issues. The workshop is still being worked on but is very close to being complete!