documentation: Update how_to_document_things_on_gitlab.md

documentation/how_to_document_things_on_gitlab.md

 # Documentation on Gitlab
 We can use Gitlab to host our documentation by exploiting the fact that Gitlab
 automatically renders Markdown (.md) files as HTML in the browser, making it
-easy to read and show images.
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+easy to read and show images.
+
+# Organization
+We will be using the top-level `README.md` as our main page for documentation.
+You might notice that this page is automatically rendered on our [main Gitlab
+project page](/../).
+
+Ideally, all documentation should be reachable from links on this main page.
+For documentation that is while-project encompassing, those links should go
+on the main page itself. For documentation that is sub-topic specific (quad,
+ground station, controls), add an appropriate link on the sub topic's README.md
+page. See the Quad section for an example.
+
+Ideally, all Markdown (.md) files should go inside some `doc` or `documentation`
+folder (with exception to the READMEs).
+
+# Editing
+If you are familiar with Markdown and Git, you can just edit the documentation
+from within your normal Git workflow.
+
+However, Gitlab also makes is relatively easy to edit Markdown pages for
+documentation right in the browser. To edit a Markdown page, select "Edit" at
+the top right. This will bring up an editor that you can use to make changes.
+To preview the final project, use the "Preview" tab at the top left. To achieve
+desired formatting, you will need to use the Markdown syntax - see the [Gitlab
+Markdown reference](https://docs.gitlab.com/ee/user/markdown.html).
+
+To create a new file within Gitlab, go to the "Repository" tab and then "Files"
+tab. As you navigate through our files, you will see a "+" (plus sign) button.
+From here, you can create a new Markdown file, upload a new file, or create a
+folder (say if you need to create some `doc` folder).