Choose between these two templates :

https://imgur.com/kBK2Biu
or
https://imgur.com/36R2beu


and basically the center circle is the face, two circles at x=25% and x=75% are the sides and the back is obviously the cut in half circle

eyes are directly 1/2 up from the bottom

nose usually is 3/8 way up from the bottom

mouth is 1/4 way up the head from the bottom

try to space the eyes so they have about even spacing between them as spacing between the edge of face so basically place the pupils about here:

You seem to accomplish shading in 1-2 strokes of the brush where it takes me 10-20 strokes and 10 undos to get anywhere close to as good shading, how do you do this? (is it just experience, or do you use references? idk?)

Do you do the same steps on all you're textures? What are they? (like coloring THEN sketching THEN detailing or something like that)

When you paint you seem to be SCULPTING the head texture while when I paint I feel like either my shading looks really plastic or it looks natural, but very 2d, how?

(nice jaw line by the way, I might steal that technique if thats ok, it maps perfectly)