Ideally, your pet should be chipped so if they ever go missing, you can track them down. If they're not, though, and your pet is lost, make sure to post a close-up and wide shot photo of them when you post flyers. Photo by Nacho
A Redditor submitted this tip, pointing out that wide shots show the animal's markings so people can clearly see any identifiable traits. People often post close up photos of the animal's face, and as one animal shelter employee points out in the thread, you want both shots so people can clearly identify your pet.
Again, it's best to just get your pets microchipped, but if you find yourself in this situation, it's something to keep in mind.