For minor changes like typos, you can click Suggest an edit to this page, located at the bottom of each article. This will take you to the source file on GitHub, where you can submit a pull request for your change through the UI.
For larger fixes, you can run the site locally with the following:
git clone https://github.com/tongueroo/jets.git cd jets/docs bundle bin/web
You'll be able to view the site on http://localhost:4000.