How to draw a face can be very simple. I generally try to think what the facial expression should be present on the character.
In this example, named Dr. Forfast, I intended to put a thoughtful expression. A good way to such a face can be to draw a hand on the chin.
First, we draw the head a little bit tilted, just strengthen the thoughtful look. We can start with an ellipse.
So we can draw a simple hand around the chin now. I am not going to go in details on how to deal with hands here, but maybe in another post.
Then we can quickly add the mouth, nose, cheek (to the left according to the reader), eyes and eyelids. For simplicity, only top eyelids are drawn. I drew the mouth not looking as smiling also not too bent as to give a sad feeling. Just in between. Of course, lines just don't come at once, I had to try until I reach the look in my mind.
I think here glasses would be perfect to place since I intended to sketch a scientist. Maybe the glasses can be a little bit old fashioned and as simple as possible. So here it is.
Before going further, lets put the eyebrows in place, again to express thoughtful look. Scowling eyebrows to name it.
Finally, I think it is time to put the hair and left ear.
Ohh, let me clear the ellipse from the very first step, and add the nape.
I dreamed this character for an amateur short story that I wrote with the name: "Start Over". It had one main character who is a scientist working on time travel. Dr. Forfast realizes some miscalculations and tries to warn the experiment group. But it was too late to stop. At the end of the story totally different result is achieved by some side effects.