I made this part in solidworks but you can make it in any CAD software.
I'm not doing teeth in this tutorial.
Step 1: Sketching
You can do a sketch that looks like mine or you can do your own.
Basically you want to make a sketch that looks like half of benders head. You don't have to make it look exactly like mine, just make it to your liking.
**YOU DO NOT WANT TO INCLUDE THE ANTENNA THAT WILL MESS UP THE PRINT**
Step 2: Revolving
Step 3: Making the Visor
Step 4: Eyes
After you have done that you want to fillet them so they look like his actual eyes. Just keep messing with the radius of the fillet to get to somewhere of your liking.
Step 5: Mouth
We need to make a copy of the front plane (by using reference geometry and selecting plane.) and move it forward towards the eyes. (Look at the picture if you need help.)
Now we need to sketch a rectangle on that plane.
You need to fillet the corners of that rectangle to 0.17 inches. it should look something like it does in one of the pictures.
Now we need to cut-extrude that rectangle. Select through all, then you should be done with the mouth!