How to draw a face (Part 1)

This is a series of blogposts I'm starting to try to help others learn how to draw as I did.  I used to do these techniques when I was initially learning portraiture from another artist that was trained in Germany.  Of course, over time, I've stopped using the guidelines, as my muscle memory seemed to train in position and guaging the proportions by eye and hand. But this is a good way to learn, as it gives discipline and helps create a good result.

I started drawing faces as a very young child, but never caught a likeness until I was ten.

After that, I was on fire! I drew constantly trying to get that almost mystical connection, the portrait that looked like whoever I was drawing...

I went to Stanley Park in Vancouver, British Columbia (Canada) constantly when I was thirteen and on vacation there one summer, learning from the portrait artists... They took pity on a young girl and let me sit and watch, and after awhile, they starting looking at what I was drawing and helping me! It was a wonderful two months...

Later on, I started selling portraits on my own (very cheaply!) to fund private art lessons to learn portraiture from a local artist where I lived, her husband was in the military, so she had originally trained with a classically educated portrait artist in Germany... She learned in the late fifties... I learned from her in the early seventies.

General sketching guidelines, explanations and tricks to train your hand and artistic eye to draw faces.  This excludes shadowing, which I will go into later.

Start with an oval (or an egg shape if that’s easier to remember) and divide it into thirds. Split in half vertically as well.  (These 'guide' lines are useful in setting the proportions of the adult face.)
Split the centre portion of your three main horizontal sections into three sections as well.

Finally, divide the vertical halves of your oval into halves again. 
Note: This process of proportional guidelines is based on a system called 'the golden mean', which was developed in renaissance times by artists.

Generally, the top of the eyebrows will line up with your top main face line labeled A in the diagram above. I've thrown in the nose and mouth on the sketch just for vanity sake here, I will go over that later on, step by step as well...

The eyebrows are centred on the secondary vertical lines f and g.  The nose and lips are centred on the middle vertical line C.

Our eyebrows actually rest at the top of the eye sockets, so you can draw in circles to represent the underlying curvature and the eyes themselves will be situated within these circles.

For illustration purposes, I am going to draw in circles to represent the eyeballs, but it's totally unnecessary to do this as a regular practice, even while you are learning, just using the general guidelines to train your hand and eye to the correct proportions is best.

Also note, these imaginary eyeballs are lined up with the inner wall of the sockets, this is because of the great rule of thumb, we all have a 'third eye' between our eyes. If you look at ninety percent of people, and use your thumb as a measuring stick to judge, you will find that the width of the space between the eyes in full front view, edge of inner tear duct to inner duct, equals the width of the eye itself.

Kind of creepy looking, isn't it? Wow! But it won't stay like that, this is just for illustration purposes.

I've divided the eye socket circles again, with a line between the centre line d and the top A and labeled the line j.

Unless we are in a horror movie, we never see the full eyeball, since they are covered top and bottom with skin and muscles.

I designated the halfway points of the eyes for illustration purposes with lines labeled h and i.

So, I've sketched in very basic eyes here, so that you can see a few things:

First, the eyebrows always extend out past the eyes; they're never lined up with the outer edge of the eyes.

Second, as long as you observe the 'third eye' distance, the viewer is more comfortable with the appearance of the face in general. It just 'feels right'.

Start changing that inner proportion and your portrait will just look wrong, wonky, and out of whack. It actually makes one feel uncomfortable when you look at it. You can make your eyes proportionally larger or smaller, just the spacing in between seems to be the most sensitive point. Most portrait artists will unconsciously slightly enlarge a person's eyes when they draw them, to make a more attractive portrait. Probably because we are all hard-wired to find children attractive, making the eyes slightly larger appeals more strongly. Children actually have larger eyes than they do once they reach their full growth. Since we're born with our final eye size and our faces grow around it as we age.

Don't go too far on enlarging the eyes to enhance the portrait, or you can end up with a cartoonish look. Too far would actually be the point where the outer edge of the eye lines up with the eyebrow end above.
Third, this is proportionality for an adult face, so our eyes are usually small compared with the size of our faces. The larger you make the eyes; the harder it is to maintain realistic proportions...

Since we aren't always shocked or surprised, the eyelid usually covers part of the iris and pupil of the eye.  (Unless of course we are looking down and the bottom section of the eye is hidden by our lower lid.)
When viewing the eye (depending on the distance), we often see the width of the lower lid due to the way it sits on the eyeball.  I often draw in a small circle or dot to represent the tear ducts, and make the upper eyelash line darker to represent the thickness and size of the lashes in comparison to the lower lashes.  I'll put in a few sparse lower lashes, but not too many or too dark, or once again, it starts looking cartoonish. A line is drawn above the upper eyelash line to represent where the upper eyelid ends. This can vary greatly, so there's no shortcut to figure out where it 'should' be.

Beneath the eye; dark shadows, bags and wrinkling will always follow the contour of how the eyeball sits in the eye socket.  This essentially mirrors the proportions of the eyelid above, so I think of it as a 'ghost lid’, I draw a partial line to identify where the edge of the curvature ends.

Since the eye surface itself is covered with fluid, it's glossy and reflects light. A good way to bring 'life' to a drawing of an eye is to leave one or two white dots on the pupil. I usually use one dot. Leave that white dot out, and the eyes usually look wrong or lifeless.
Pupil size can vary greatly due to lighting conditions, in bright light, the pupil can be quite small, in low light conditions, and it can be quite large. I generally like to go for the midrange; it gives a more attractive and realistic result.

(If you are drawing from a photograph as a reference and a flash was used, the pupils will be smaller than normal.

To make your drawing more realistic, I'd recommend drawing the pupils larger to give a pleasing result.)  

As the eye gazes in different directions, it moves partially out of sight under the upper eyelid and the rest of the face. 

This means we rarely ever view the whole circle of the eye (where the eye in this case refers to iris and pupil), so we are always drawing partially to represent this. 

When drawing the face, keep in mind the viewing distance you are working with in your image.
If you are close, you'll see a suggestion of lower lashes, width of lower lid and tear duct on the inner corner.

The further away, the more indistinct the details become. Drawing in eyelashes on a distance drawing of the face, appears very cartoonish and unrealistic.