You can add new slides through Slider → Add 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 image will be displayed in the header of the page, the required dimensions: (1920 x 800)
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.
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.