it's a matter of technique. It takes PRACTICAL effects, i.e. there are no fancy third-party plugins that can do it for you, you have to do some of this so it shows up on the camera.
Get something that rotates -- a big turntable, for example -- that can accommodate the subject.
Place the subject's neck in line with the point of rotation.
Rotate the turntable.
Depending on the speed of rotation you want, you may have to play with Time Remapping. But PLAN for it -- don't guess at it. Then you can mask the subject's head onto the subject's body... which you have shot previously, and which you have matched to the rotation shot for exposure, camera position, etc.
This special effects stuff gets involved. It takes planning. You just can't wing it, and pray for a miracle using the software.
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA