Golding's writing style is rich in detail and layered with meanings and universal truths. The prose which he uses to describe the island, for example, is so rich in detail that it makes the island central to the tone of the book and the events that take place.
Up there, for once, were clouds, great bulging towers that sprouted away over the island, grey and cream and copper-colored. The clouds were sitting on the land; they squeezed, produced moment by moment this close, tormenting heat. (8.210)
The darker aspects of his work give the entire work the feeling of oppression, or impending doom. Here's a great example of that:
The pile of guts was a black blob of flies that buzzed like a saw. After a while these flies found Simon. Gorged, they alighted by his runnels of sweat and drank. They tickled under his nostrils and played leapfrog on his thighs. They were black and iridescent green and without number; and in front of Simon, the Lord of the Flies hung on his stick and grinned. (8.210)