In William Golding's Lord of the Flies, how does Jack paint his face in Chapter 4?

Kneeling beside a pool of water in order to see his reflection, Jack uses a combination of red clay, white clay, and charcoal to paint his face. As the boys are on an island, the ingredients used for Jack's mask must be (as you might have guessed) naturally sourced. While we must rely on our imaginations to visualize the exact nature of Jack's face paint, we can reasonably assume that he is camouflaging himself in a way that he hopes will make him harder to detect. Consider the following passage in Chapter 4 of the text:

“If only I’d some green!”
He turned a half-concealed face up to Roger and answered the incomprehension of his gaze.
“For hunting. Like in the war. You know—dazzle paint. Like things trying to look like something else—”
He twisted in the urgency of telling. “—like moths on a tree trunk" (Golding, Chapter 4)

In Jack's explanation, we see that his intention is to be unrecognizable. By looking like something else, Jack might become better suited to hunting, but the underlying effect of covering his face is that he simultaneously covers aspects of himself and his identity. Not satisfied with the first attempt at his mask, Jack decides to try another pattern, one which is decidedly more aggressive than the first. Consider, for example, the following excerpt from Golding's text:

Jack planned his new face. He made one cheek and one eye-socket white, then he rubbed red over the other half of his face and slashed a black bar of charcoal across from right ear to left jaw. He looked in the pool for his reflection, but his breathing troubled the mirror (Golding, Chapter 4). 

In Golding's language, we see tones of aggression and violence which foreshadow Jack's change of behavior. Jack does not merely draw; rather, he "slash[es]" (Golding). In the image of the white eye socket, we easily imagine skeletal structures. Jack transforms through charcoal and clay into a figure who, no longer acting as "Jack", may behave as wildly, violently, or erratically as he chooses. Golding, writing on this transformation, states:

He looked in astonishment, no longer at himself but at an awesome stranger. He spilt the water and leapt to his feet, laughing excitedly. Beside the pool his sinewy body held up a mask that drew their eyes and appalled them. He began to dance and his laughter became a bloodthirsty snarling (Golding, Chapter 4).

Once adorned with the mask, Jack becomes an "awesome stranger" (meaning that he is capable of inspiring "awe" in others). Jack's shift is a powerful one: he no longer recognizes himself and no longer shows concern for his actions. The boys regard his painted face in a manner importantly described as a state of being "appalled" rather than impressed or intrigued. The scene focuses, then, on the ways in which identity might be lost or suppressed, how reality might be "masked" or covered, and the ways in which behaviors might change when accountability is removed. Because he no longer acts as "Jack" in the scene, Jack does not claim responsibility for the violence of his actions or his behaviors.

(Golding, William. The Lord of the Flies.)