Adding an attachment such as an image or link can be done while creating an alert, poll, or form.
Important Note:
Adding the attachment as a link in the body of the message is recommended so the attachment is accessible to the public link, email, and app notifications (if applicable).
Instructions
In the Message section, select the Link icon:

Select Browse Server:

Upload a new file or choose a file already in the system:

Click Submit:

Make any adjustments to the Display Text:

Click OK:

The link to the attachment will show in the body of the message:
