Get started with API Designer

I have tried to start with the API Designer and I could compile locally, start a local API server, ...

There is also an installed ApiServer on our IIS.

But I can't find out how to do any further fist step.

Is there any "getting started" document or video for API Designer?
Just provide me all the steps to get a single "Hello World" or something like that.

Patrick

I have Identity Manager 8.1.3