download and manual :
This script for Daz Studio will take care of posing the head, and optionally, the neck, chest, abdomen and hip, so that the face faces the current camera.
This script was suggested by Daz Forums member Tugpsx
Select a figure’s head.
launch the script
it looks like this
select the playrange to be processed.
Select the bones (other than the head ) that participate in the twisting of the body required to bring the face to face the camera.
click on the Doit buttom