You can add new slides through Slides → Add New Slide in the WordPress Administration Panel.
Slides are limited to only a certain subset of the options of standard posts, because they don’t contain any real content.
Slide image
The featured image is used as the background for the slide. Select a wide but short image, around 1680px x 275px. Click the + button to upload an image.
Unhighlighted title
The unhighlighted slide title is used as the main text on the slide.(1)
Highlighted title
Highligted part of the slide title.(1)
Subtitle
Write the subtitle.(2)
Content
Insert the main content displayed on the slide.(3)
Action button text
This is the content of the button used to link to another post or external page. Keep this field empty if you don’t want to display a button.(4)
Action button URL
This is the URL linking to another post or external page. Keep this field empty if you don’t want to display a button.