Digital Photo booths have become so popular that many people have some peripheral experience with them even if they haven't personally used one.
No doubt you've seen the typical arrangement of photo booth stick props: Mustaches, glasses, hats, all on a stick. These can be great fun but they can also be kinda...bleh.
If you're providing your own props for a photo booth you can really make things a lot more fun if you look into finding creative, fun props. A few great places to find interesting and inexpensive props would be thrift stores and garage sales. Here you can find items that may be useless to someone else but would be really fun and quirky to include in your photo booth. You could go home with bags full of items for less than $30.
One thing to keep in mind if you include any "mask" props however, is that you won't be able to see the face of the person wearing the mask in any of the photos! This can be fun and cute at first, however after scrolling through many of your photos you'll just keep seeing the same mask over and over again, when really you'd probably rather be able to see the person's facial expressions. Especially if they're wearing a silly hat, glasses, or a wig!
If you are a fan of the more traditional stick props. There are many places to choose from online. You can start here at amazon.