How to show the post featured image in the post content with the Hueman theme ?

WordPress allows you to set a featured image, also called post thumbnail, when you publish a post. ( How to set a featured image (thumbnail) to a page or post in WordPress ? ) 

In the  Hueman theme, you can display the featured image of a post between the heading and the content, like in the picture below. ( Live example here )

How ?

When editing your post, select the image post format, like on the screenshot hereafter. And the hit the publish or update button.