Add the posts,pages and/or media library images to the slider. You would get ‘Add to Dbox Lite Slider’ checkbox on the edit panel (of post/page/image) after plugin activation.
Go to slider settings -> Change the width of the slider and the height of the slider, depending on your theme width and your requirement. You can change other parameters like colors, borders, font styles and whether to show the post content or not etc.
Now you can insert the Dbox Lite Slider on your WordPress site using either the template tag or the shortcode mentioned in preview tab of Dbox Lite slider settings or you can use widget for displaying slider on your site.