exporting enhanced podcast to share

Trying to help my daughter share an enhanced podcast created in Garageband with her friends. We have exported the file using AAC conversion. We have an .mp4 file. Whats next? She wants to post the file for viewing on facebook. It is a podcast featuring music and photos. However, I cant seem to see the photos in anything but garageband Any help is appreciated! This is our first mac and we are learning together!