How do you not leave fingerprints on polymer clay?

If you don't want to leave fingerprints on the clay, there are two things you can do.

The first is to wear surgical gloves when you handle the clay.

The other is to clean the surface with a baby wipe before curing.

And, of course, you can sand them off after curing as well, but that is a bit of a work, so I prefer the baby wipes myself.

You can wear those rubber gloves, or you can you use plastic wrap to kind of wrap the clay to smooth out the fingerprints.