In Hypermedia there are three main entities: Documents, Accounts and Groups. The purpose of groups is to serve as a collection of Documents and people that you can subscribe to get relevant information about the group's topic. It also makes it possible to access the content inside the Hypermedia network via Sites.
To create your first group, you need to go to the Groups section of the app, and click in the top right button that says "New group". You'll see a dialog form where you can add the title and the description of your group. after you fill the information and click submit, you will be redirected to your groups page.
Now let's go out the app and start setting up the server for our group to be published.