I've been trying to figure this out to no avail, how do you create a story with multiple authors? I've seen it done here, but can't figure out how to do it myself.

I assume you know how to create a story in the first place.

From the Home page, click 'Write a New Story' above the left side bar.
On the create page, under 'Collaborators' click on co-writer -- a drop down will appear asking how many collaborators you want, up to a maximum of five. When you create your story, it will open it up to invite collaborators / other members can apply to join your story.'

I hope that helps.

Not really, I just realized I should be more detailed in what I'm trying to do xd, or rather, where... Since I have no internet on my PC, I use the mobile penana app, which apparently doen't have the option for that xd.