One of the greatest tools to use with polymer clay is a bench polisher. Your pieces will need a little sanding (or more if there are imperfections). You can find very fine sandpaper at auto care stores.
There are other ways to put a shine on the clay, but this is fast, simple, and doesn’t make a sticky stinky mess. Just make sure to have a “back stop” so when the wheel grabs your work it won’t fly across the room.