How to Activate Tightknit in New Slack Channels Using Tightknit Studio for Public but Hidden Settings

One more! The docs show how to activate Tightknit in a new Slack channel in the old UI. How do we do it in Tightknit Studio? I'm making 40-50 new channels and I want them to be:

(Reason for that huge # -- it's a Slack channel for each city where we have an IRL member club)