Runner install on Kubernetes seems to have circular dependency

When looking into registering a gitlab runner we can see the requirements say we need to have gitlab runner installed already on a separate server. OK, so we go to the install gitlab runner page and select install on Kubernetes. But on that page there is a note about a token parameter we need to set in our ConfigMap:

Note: The token can be found in /etc/gitlab-runner/config.toml and should have been generated after registering the Runner. It’s not to be confused with the registration token that can be found under your project’s Settings > CI/CD > Runners settings .

Flipping back to the page on how to register a runner, it doesn’t seem clear how we can do that without having a runner installed already.

Am I missing something? Is there a guide or blog post somewhere on how to install runners on Kube from start to finish?