To create a new Article, under Administration toolbar choose Content > Add content > Article. (
In the teaser section you can add Teaser Image and Teaser Text. The teaser text and the image are used for article teasers. Additionally, they are used for Facebook, Twitter and other social snippets,
Click on the Select Image button to select a teaser image for the article. You can import a new image or you can use an existing image from your library.
After choosing the image, you can click on the "Edit" button and use Focal Point to specify the portion of an image that is most important. For example, this will prevent thumbnail that cuts off the subject's head.
You will notice a crosshair in the middle of the image. Drag this crosshair to the most important part of your image. Alternatively you can click on the important part of your image if dragging seems too daunting.
The classic Body field is replaced with a Paragraph Builder as a new way of content creation. This will make things cleaner and will give you more editing power and flexibility. Instead of putting all the content in one WYSIWYG body field including images and videos, you can now choose on-the-fly between pre-defined Paragraph Types independent from one another.
To add new paragraph click on the "Add paragraph" button and from the pop-up choose which type of paragraph you wish to add.
Use Publishing Options to promote your article on the front page, added it to the Featured Slider or in the Editor's Picks block.