The image widget allows you to add images when editing a template.
Find the template you want to add an image to, click the cog next to its name in your dashboard, and then click “Edit this template” from the menu on the right.
Next select the task to add an image to by clicking on it. Then select “Image” from the right-hand menu.
This will create an empty image widget at the bottom of the task you are viewing. Click the “Upload an image” button to upload your image of choice.
Alternatively, you can create an image widget by dragging and dropping (or copy and pasting) an image into the task whilst editing.