Sign into https://studio.gobistories.com/.
Create a new story.
Upload short videos and images to your story.
Publish the story.
Inside your WordPress editor, find a HTML Widget.
Paste in the generated code from step 3 and apply the changes.
Stories should now be visible in the preview of your page.
If you you can't find a way to add HTML in your WordPress editor, you can also use short codes as described here.