Document how to release

Author: psrpinto

CONTRIBUTING.md

@@ -14,3 +14,26 @@ wp-env run cli "wp rewrite structure '/%postname%'"
 ```
 
 The site is now available at http://localhost:8888.
+
+
+## Release
+Plugin releases are automatically created through a GitHub Action, which is executed whenever a tag of the form `vX.Y.Z` is pushed. You can create and push a tag as follows.
+
+First find the latest tag:
+
+```shell
+# Fetch tags from origin
+git fetch
+
+# Returns the latest tag, e.g. v0.1.0
+git describe --tags --abbrev=0
+```
+
+Then create and push a tag that increments the latest one as per [Semantic Versioning](https://semver.org/):
+
+```shell
+git tag v0.1.1
+git push origin v0.1.1
+```
+
+The [GitHub Action](https://github.com/Automattic/wp-openid-connect-server/actions) will launch automatically, and when completed will have created a **draft release** for the tag that was pushed. You should then edit that release to provide a meaningful title and description (ideally including a [changelog](https://keepachangelog.com/en/1.0.0/)), then publish the release.