Hello Caryn. Thanks for your interest. This new publication is a bit different than most in that it accepts as writers only editors and owners of Medium publications or writers who have suggestions for these editors and owners in how to improve a publication, attract more writers or engage more readers. Are you already an editor/owner, or do you have suggestions for editors/owners? As newbie, you just might, and you might have suggestions that people who have been on Medium longer wouldn’t think of.
If not, I wish you luck as a writer on Medium. If you want a more comprehensive submissions guide, you might want to check out the submissions guide for Politically Speaking, where I am an editor. Ignore the parts that are geared toward politics, and you'll have something that applies everywhere in Medium. The guide is at https://medium.com/politically-speaking/submission-guidelines-d6d0c14bdd6f?source=friends_link&sk=87be693a9b538d0d8b72f1fc742159f0