The document provides instructions for laying out a basic webpage using CSS and dividing the page into sections with <div> tags. It begins with the raw HTML structure and then incrementally adds CSS styling rules to control the visual layout and formatting. Key steps include centering the main content container, floating elements like headers and sidebars, clearing floats to prevent overlapping content, and styling text and links. The end result is a multi-column page layout with header, content area, sidebar, and footer sections formatted using CSS positioning and styling.