Is there a tutorial/template to follow for module documentation on wiki? Or should I just copy one that I like and change relevant sections?
We’ll start transitioning the documentation to ReadTheDocs. It will allow keeping documentation and code in sync, generating off-line documentation in various formats (pdf, epub, mobile-friendly html, …), including documentation in the installation package, receiving documentation updates via GitHub the same way as software contributions, using the same mechanism to document extensions (source code and documentation of extensions can be hosted in the same repository, fully managed by the extension developers). See some more details in this topic: Document modules on readthedocs
You can still write documentation on the wiki, using the current wiki template and it’ll be updated when the documentation is moved to readthedocs. Or, you can write your documentation on readthedocs and help us with developing the new template.