How to Attach Images to Points in a Feature Service? - For StoryMaps

[TarekKoudmani]

Hi all, I'm looking to add images to individual points on a story map I've created, but is turning out to be far more difficult than I had planned.

From ArcGIS Pro I have uploaded a web layer to my organization's ESRI account that contains a basemap, and a shapefile with a series of points. I have then added that web layer to StoryMaps as a Map Tour via Feature Service. This is where I am stuck, I don't know how to input images to fill in the media tile on the StoryMaps page.

I have done a lot of searching around and found that I think what I'm looking to do is: attaching an image directly to the feature service, because it cannot be done through StoryMaps itself. It sounds like this happens through the contents pane on my ESRI online account, but I'm not sure.

Does anyone know how to attach an image to the feature service directly?

The ESRI example has what I'm looking to do, with images corresponding to each point, as seen below. 

Thanks!