The previous steps of animation and video had sound effects so this step isn’t entirely new. However, variety and repetition are important to overcome the phobia so here are additional auditory exposures.
First is a link to a website with throwing up sound effects. They are all relatively brief (less than half a minute for most) and there is a great deal of variety. The page doesn’t have any hierarchy, so there isn’t a way to put them in order of increasing challenge other than the length of the clip. At this point in the process, listening to them somewhat randomly is beneficial anyway.
This is about 10 minutes of the sound of people throwing up. There is some variation. The image doesn’t change.