This blog contains a simple steps on how to use and insert instax mini film to Instax Mini 25s.
For first time use make sure that the battery was already inserted on the side of the camera.
5. Slide the "FILM" switch on the side of the camera to open the back where you need to put in the film.
8. Close the back cover of the camera. You should be able to see from the yellow mark on the small glass hole at the camera's back.
Now you're almost done with the preparation for your first instax photo.
Now you are ready to shoot! Just click the shutter button and you're instax photos will be develop in minutes right before your very eyes!