docs: add release guide

README.md

@@ -12,7 +12,24 @@ This repository contains the web frontend for the ProvideQ toolbox.
    You can disable the data collection using `yarn exec next telemetry disable`.
 5. Use `yarn dev` to spin up a local development server
 
+## Releasing a new version
+1. Create a release branch from develop: `git checkout -b release/x.y.z`.
+2. Bump the version number in the `package.json` file to the new version number
+   and commit it to the release branch.
+3. Push to GitHub and create a pull request to merge the release branch into
+   `main`.
+4. Make sure to test your new version!
+5. Write a changelog.
+   The PR can help you identify differences between the last release (`main`)
+   and the next one (your release branch).
+6. Merge the PR into main.
+7. [Create a new GitHub release](https://github.com/ProvideQ/toolbox-web/releases/new) with a new tag named like your
+   version number `x.y.z` and use the changelog as the description.
+9. Pull the main branch (`git checkout main && git pull`), merge it into the
+   develop branch (`git checkout develop && git pull && git merge main`) and
+   push it (`git push`).
+
 ## License
-Copyright (c) 2022 ProvideQ
+Copyright (c) 2022 - 2023 ProvideQ
 
 This project is available under the [MIT License](./LICENSE)