To create a story in the Vocal network, you need to create an account and sign in.
Once you are signed in, you can click on "Create Story" from the upper right corner of the screen.
You'll be brought to the Vocal editor, which looks like this:
Remember to always "Save Changes" while you are creating your story.
When you're finished, you can either "Submit for Review" or return to drafts (where you can submit it later).