This is my favorite project for teaching the basics of prisma, as it makes the process a lot less daunting.
I usually preface this project by showing them a tutorial of burnishing and blending with prisma, so they can see the process in action. I create my own videos and post them to Canvas where they can refer back to them if need be.
Then I give them a page from a magazine and they cut the magazine into strips. National Geographic has the best full-page images with slightly smaller page sizes, so that is what I have used each time I've done this project. After cutting the page into strips, students place the strips on a sheet of toned paper and remove every other one, making sure the remaining strips stay perfectly in place. These are glued to the paper leaving gaps where the students can draw. It's important that they hold onto the "missing" strips to use as references. Providing a ziplock baggie helps.
Click to cycle through the examples below: