Each Taming the BEAST tutorials lives in its own public GitHub repository. The repository contains, in addition to the tutorial, also all the data files and scripts needed to run the tutorial as well as example BEAST2 XML files and output files from running the tutorial. This means that each tutorial is a standalone unit that can be downloaded by anyone with an internet connection. And since the output is bundled with the tutorial, this makes it easy to check that you're doing the tutorial in the right way!
The collaborative nature of GitHub also makes it easy for anyone who spots an error in a tutorial to report or correct it. Additionally, anyone who updated or extended a tutorial for a class or a workshop can easily upload the changes to the repository. Since Git keeps a history of all the tutorial files you can also easily see when a tutorial was last updated, and access old versions.
Most of the tutorial repositories belong to the Taming the BEAST organization on GitHub, but this is not a requirement and in some cases authors retain ownership of their tutorials. This makes it possible for anyone to contribute a new tutorial, but still retain ownership and credit. As long as the tutorial conforms to a few guidelines, there is no need to transfer ownership to Taming the BEAST.
Submitting a new tutorial to Taming the BEAST comprises the following three steps (described in more detail below):