Now, there are many ways done by themes to add a post to a slider. One way is to create a specific slider custom post type. Another is to add something to the post’s custom field. Forever theme shows us an easier way to do it:
Featuring posts in a slider on your home page is easy. You just need sticky posts with Featured Images. Every sticky post you have (up to 10) that has a Featured Image (at least 887 pixels wide) attached will show up there. Easy!
Easy indeed! Sticky post and featured image are both built-in features of WordPress, so there’s a good chance that users are already familiar with it. There’s no need to create separate options, just a couple familiar steps on the Edit Post dashboard area and the user is done. I bet the ordering of the slider can be done simply by changing the post’s date too, so there’s no need to create another interface for it.
This is simple, familiar, and easy. Good idea.