You may have noticed that this site's navigation is divided partly into subsections, with labels like "Writing". **Infusion** (or, rather, Hugo) allows you to create such subsections by simply nesting folders under the `/patterns` folder. In the following example, I have a subsection about different types of "popup" pattern.
Note that subfolders like `/popups` must each have an `_index.md` file. This file doesn't need any content except the TOML metadata defining the title (name) of that subsection:
```
+++
title = "Popups"
+++
```
The `/patterns` folder itself does not need indexing explicitly in this way.
**Infusion** does not currently support _sub_-subsections.
Now that you know where to put everything, it's time to talk about how to actually write individual patterns. Don't worry, it's pretty straightforward. Turn to {{% pattern "Markdown & metadata" %}}.