The boys arrive in their uniform school gear, representative of the ordered society they have left. When Ralph appears, he carries his school sweater and pulls at his stockings. The boys' uniform black shoes are covered in sand almost immediately. When the conch brings the group together, they still physically hold the symbolic remnants of their old and structured lives:

They were naked and carrying their clothes; others half-naked, or more or less dressed, in school uniforms, grey, blue, fawn, jacketed, or jerseyed. There were badges, mottoes even, stripes of color in stockings and pullovers.

By chapter 7, Ralph's appearance has changed dramatically:

He would like to have a pair of scissors and cut this hair—he flung the mass back—cut this filthy hair right back to half an inch. He would like to have a bath, a proper wallow with soap. He passed his tongue experimentally over his teeth and decided that a toothbrush would come in handy too. Then there were his nails—

At this point, the boys are losing their sense of physical structure associated with civilization. There is no barber, no toothpaste, no soap. They become unkempt and disheveled, becoming more physically uncivilized with each passing day.

When the boys first gather as a group, they recognize the need for order on the island. They are willing to submit to a democratic sense of order and follow the outcome of their impromptu election:

“All right. Who wants Jack for chief?”

With dreary obedience the choir raised their hands.

“Who wants me?”

Every hand outside the choir except Piggy’s was raised immediately. Then Piggy, too, raised his hand grudgingly into the air. Ralph counted. “I’m chief then.”

The circle of boys broke into applause. Even the choir applauded...

Although Jack campaigns to be their leader, he isn't elected; interestingly, even his choir at this point is willing to follow democratic responsibilities and recognize Ralph as their rightful leader.

Near the end, of course, this falls apart. Piggy is left as Ralph's lone supporter after the group murders Simon—and Ralph and Piggy participate in this act indirectly. The group murders Piggy and tries to murder Ralph, intent on destroying everything that symbolizes civilization and order. They become thieves, bloodthirsty savages, and rage-driven boys who almost destroy the entire island and themselves before they are rescued.

At the beginning of the story, the boys are relatively cooperative and positive with one another as they attempt to create a civilized society on the uninhabited island. Initially, the boys' hair is fairly groomed, and their clothing is intact. As the story progresses, Golding illustrates the boys' descent into savagery by depicting the length of their hair and lack of clothing, which are symbolic remnants of civilized society.

At the beginning of chapter 3, Golding depicts Jack's change in appearance and behavior as he attempts to track a pig. Golding writes,

"[Jack's] sandy hair, considerably longer than it had been when they dropped in, was lighter now; and his bare back was a mass of dark freckles and peeling sunburn. A sharpened stick about five feet long trailed from his right hand, and except for a pair of tattered shorts held up by his knife-belt he was naked" (36).

While Jack and the other boys slowly begin to disobey Ralph's authority, they also allow their hair to grow and begin to strip away their articles of clothing. Jack dismisses the importance of a signal fire and only focuses on hunting, which is a primitive instinct. In chapter 4, Jack and his hunters begin painting their faces, which emboldens them to act like savages without feeling self-conscious about their behavior.

In contrast, Ralph routinely bathes and continually attempts to keep his hair out of his eyes by pushing it back. Towards the end of the story, Jack and his band of savages run around naked with their faces painted, intimidating and threatening Ralph and his followers. Eventually, the boys end up murdering Simon and Piggy, and Jack gives his savages the order to kill Ralph. Fortunately, Ralph avoids the savages and is saved when a British Naval officer discovers them on a beach. 

The change in the boys' appearances from neatly uniformed private school boys to ragged, scraggly-haired savages follows the change in the boys' behavior.  As their appearance degrades, so does their behavior.  At the start of chapter 5, Ralph, the narration tells us, "...discovered dirt and decay, understood how much he disliked perpetually flicking the tangled hair out of his eyes,...".  At the beginning of chapter 7, we are told, "He [Ralph] would like to have a pair of scissors and cut his hair....he would like to have a bath....and decided that a toothbrush would come in handy too."  Ralph constantly laments his degradation in appearance and cleanliness.  The worse his appearance becomes, the more he wishes he could be clean and well-groomed again.  The other boys are also experiencing the same lack of cleanliness and neatness.  By the end of the book, their clothes are barely hanging on their near-naked bodies because their clothes are in tatters.  Jack is described, in chapter 10, when he conducts a meeting as being "naked to the waist".  He is one of the most savage on the island and he seems to revel in his appearance, even going so far as to rub mud and ashes on his face, making himself even dirtier.  This trend away from civilized clothing and appearance mirrors the trend away from civilized behavior and attitude.  In chapter 1, Jack hesitates when he has the chance to kill a pig and loses the pig.  He hesitates because he is still civilized. The next time he sees a pig, just as he vowed in chapter 1, he does not hesitate because he has become more savage.  In chapter 4, Roger - who becomes the most savage of all of the boys on the island - throws stones at Henry, but purposely misses him. "Here, invisible yet strong, was the taboo of the old life."  The "taboo" referred to is civilized behavior of not bullying.  The narration lets us know that this taboo will be broken though by use of the term "old life" meaning that a "new life" will replace it and along with it, a new society - one that is savage in nature.  By the end of the story, the boys have all become savage as they hunt Ralph who has to think and act like a wild animal so that he can survive.