How To Setup Featured Image
To set up post thumbnails, you should use the “Featured image” option of WordPress. For best visual appearance, the minimum dimension of the thumbnails should be a 400px x 270px
- Go to Dashboard-> Posts / Pages
- Select the post or page you want to set image thumbnails
- On the bottom right there is a “Featured Image” box
- Click “Set Featured Image” and Select image
- Publish/ Update the Post