Buy this coloured paper and place it over the front of the camera you are using for your photo booth. When you take pictures, everyone and everything in the photo will be covered in your chosen hue. To protect your camera, make sure you cover the lens with it, but don't secure it to the lens itself; attach it to the hardware on the camera or phone using some nonabrasive Blu Tack or tape.
This effect is perfect if you're in a really dark space and don't want to spend money on lighting equipment. If the room is dark, it can actually add more dimension to the photo. It also looks really stylish and extremely Instagram worthy.