Hey Heather, thought it might be easier to build a quick webpage to explain the process.
For the Creative Multicare Trade Shows, we provide a Green Screen Photo Booth with instant 4x6 inch prints that are based on the Theme for each trade show and that have branding for Creative Multicare at the bottom of the prints.
We try to give 4 or 5 different digital backdrops that each group of guests may chose from prior to the photos be taken.
Here is Atlanta Trade Show is 2018 and the theme as Fairy Tales.
Here is the green screen setup.
Guests stand in front of the green screen and see themselves with the backdrop of there choice. Here is a GIF the shows what I'm talking about