When you are beginning to draw a portrait the first, all-important step is to establish the overall outside shape of the head. Most artists call the outside shape the contour, envelope is also used. I prefer to call this initial step striking the arabesque. This entails accurately gauging both the height/width proportion and the actual shape.
It takes the trained artist less than 30 seconds to sketch in that outside shape ... it is a lightning quick dash that speaks more of a fast paced dance than a laborious study. If terminology implies intent then arabesque fits the bill.
The likeness of your portrait is determined by that initial big shape. Everything else is subservient to it. From there it is a matter of breaking down the big shape into the smaller corresponding shapes such as the features, hair, neck, etc.
No one is born with this skill. We all have had to acquire it.
