Where do I find this? There’s a badge for completing it on the badge page, but I couldn’t seem hit on it by searching the Talk site.
Your first private message on the talk site (click your avatar and then the envelope icon) should be a message from “discobot”. Reply to its message to kick off the tutorial. (I know, it’s not super obvious… it took me a few weeks to realize that wasn’t just a “Welcome” message, but had some smarts to it.)