After having extracted the joint by using delete by type < history, leave the eyes by going to delete all by type < history to get rid of any association.
Rename all the layers and then you can edit the object using the Shape editor.
Select the head < create a blend shape < add target < rename the parts you are going to modify to have a tidy animation
Create a facial expression using the grab tool under the voice sculpting and start modeling the geometry (pay attention to the falloff and use the Smooth Target tool).
Add another target for the nose < name it as nasal < tool setting < turn the symmetry on and start model with the Grab Tool.
Before going to modify the mouth geometry go to the tool setting < falloff < surface. This helps us modify only the surface of the lips.
Inflate the cheeks to make it looks realistic.
When you are happy go to Rigging < Skeleton < create joints and be sure that, in Shading, X-Ray Joints is active.
Go to the side view and create your joints. Name your joints properly so that the pivot points will control the head.
Select base neck – head rotate and jaw rotate < CTRL Shift and select the head < go to skin < bind skin < bind to selected joints < apply
To make the eyes and the teeth follow the rigging, select the eyes < ctrl group < select head rotate < parent constrain < maintain offset on < apply
Afterward, select the object < go to skin < paint skin weight
Try to see if the paint weight was properly applied
Set some controllers for the joints < add as many circles NURBS as needed < snap each one to its joint < constrain < parent each control to its joint
To restrict the animation go to attribute editor < under jaw ctrl < open limit information in order to limit the movement of the joint.
Do the same for the others
Here I added more facial expressions in the shape editor
Then go to rendering, adjust all the setting required to create a exr file and create a render to composite it on Nuke.