There are two ways that you can pair an image to a link within Twitter.
Tweet A Link Post
In the "Add Content" field you can choose to share link content to Twitter. We'll pull in all the OG tag detail and show you a preview on the right.
You can '@', hashtag and customize your post text within the preview on the right. Twitter does not allow anyone, even natively within Twitter, to change the Twitter Image Card.
Tweet An Image
If you would like to pair a custom image with your link, we recommend sharing an image when you click "Add Content." Choose the image that you want to pair with the link from your library or upload it directly from your computer.
In the image's post text, you can then share the link that you want to direct to in the post text field.