This was based on real proportions I studied from various photos, all with the models looking straight and with pretty much the same camera angle.
First I start by drawing a circle then I add half of the circle below for the rest of the face. The nose ends up below the circle. Of course you don't need to start this way, you can just draw an upside down egg shape. Then add both horizontal and vertical lines dividing the face.PROPORTIONS: 1 -
The eyes are often in the middle of the head, I like to draw them right above the horizontal centerline.2-
Most of the time there's 1 eye width between the eyes. It can be a little less if the person has big eyes and a little more if the eyes are small, but it's usually 1 eye regardless of the eyes' size.3 -
The space after the outer corner of the eye is a little bit more than 1/2 eye. Some people say that the face has 5 eyes width (eyes, 1 eye between them and 1 eye after each outer eye corner), but none of the persons I studied had the face large like that.4 -
The nose usually lines up with the tear ducts, but you can draw it lining up with the inner corners of the eyes, it won't make too much of a difference.5 -
The mouth size can vary very much from person to person, but most of people have an "average mouth", with the corner lined up with the inner side of the iris. Some say that the corners of the mouth are lined up with the center of the eyes (pupils) but that is just for big mouths which is not that common.6 -
The top of the ear lines up with the eyebrows or the top of the eyes; the bottom of the ear lines up with the nose or it can be a bit above. Just keep in mind that if you draw a female with a big distance between brows and eyes it's better align the ear with the top of the eyes instead the brows.7 -
The "eyebrows' scheme" is something used to do eyebrows in real life, I like to use it in drawing for symmetrical (female) eyebrows. First I make a vertical line from the nostril to find the start of the brow; then a line from the corner of the nose passing by the outer corner of the eye to find the end of the brow. Then I do another line from the nostril passing by the center of the eyes to find the eyebrow arch.
The forehead is 1/3 of the face (the face not the head, don't count the space above the forehead); from the brows to the nose: 1/3 of the face; from the nose to the chin: 1/3 of the face. Not everyone fit in this but I find it's a useful measurement.DIFFERENCE BETWEEN MALE AND FEMALE
males have wider jaw and neck and more angular features while females have delicate features
males usually have bigger nose and mouth and smaller eyes and lips than females
men have straight and thicker eyebrows and they're very next to the eyes
Go here for male and female body proportions fav.me/d609pik