You just send it for developing at Ruby or FotoHub, and tell them that you want it mounted. Unless you want to save money and DIY, then yes, cut it out and sandwich the slide between the mounts (frame).
the lab will have to take out the slide mount for making prints, but may have problem mounting it back, cos most of the slide mount is not reusable type.
the lab will have to take out the slide mount for making prints, but may have problem mounting it back, cos most of the slide mount is not reusable type.