Just like all other Communities on Hive, there is a "subscribe" button at the top of the page (at least on computer, not sure about mobile) and members can publish a post to the Community.

The focus of InnerBlocks is all the myriad "blocks" that make each of us unique — our skills, interests, hobbies, education, culture, anything that makes us who we are. Inner blocks is all about people and their stories, so if someone tells us a little about "who they are" in a post, we're interested in curating them. The project is not concerned with technical content, masterful photography, and other topics that do not speak of the author and how they live their lives. The focus, instead, is stories about people, who we are, and #lifehappening 🙂