Start by cloning this repo, or just grab a copy of the file makeone.pony, and compile it using ponyc.
Then get your local clone of the Pony tutorial, in a suitable folder:
git clone https://github.com/CausalityLtd/pony-tutorial.git
Then, assuming your compiled program is named "onedoc-md", you should be able to do something like this:
./onedoc-md /PATH/TO/pony-tutorial /PATH/TO/one.md
The file "one.md" now contains the entire Pony tutorial.
To convert this "one.md" into a HTML file, I suggest you use marked, which you can install using npm.
When you've got the raw HTML file, you may insert its contents into a copy of the file src/doc-css.html to get a complete HTML document, including CSS that more or less matches the online Pony tutorial.
If you want to directly produce a quick PDF of the "one.md", you may try this one: