Explain how to add InnerSource Stories in CONTRIBUTING.md (#686)

* Explain how to add InnerSource Stories in CONTRIBUTING.md
* Linking to GitHub PR Guidelines

---------

Co-authored-by: Jeff Bailey <776901+jeffabailey@users.noreply.github.com>

Author: spier

CONTRIBUTING.md

@@ -8,6 +8,15 @@ Contributions to this repo are welcome. Please follow the following guidelines:
 * Make your proposed changes inside your fork.
 * Test your build locally.
 * Commit to your fork.
-* Follow the GitHub Guidelines on creating a pull request.
+* Follow the [GitHub Pull Request Guidelines](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request) to create a pull request.
 * Please be as descriptive as necessary in your PR.
 * For i18n contributors, we recommend reading [the instructions on how it works](i18n.md).
+
+## Adding "InnerSource Stories"
+
+When adding a new organization on the [InnerSource Stories](https://innersourcecommons.org/stories/) page, please follow these steps:
+
+* Provide some evidence of the use of InnerSource practices at the given organization. Optimally an online reference that you can link to.
+* Get confirmation from the organization that they are happy to be listed on the Stories page.
+
+Here's an [example PR](https://github.com/InnerSourceCommons/innersourcecommons.org/pull/683) demonstrating this.