On-page SEO involves optimizing individual web pages to rank higher in search engines. Key on-page factors include page titles, meta descriptions, URLs, content, images, links, and site structure. The document provides guidelines for optimizing each of these elements, such as using keywords in titles, unique and keyword-rich content, alt text for images, an XML sitemap, and internal do-follow links. Regular on-page optimization over 6-12 months is recommended for improving search engine rankings. Things to avoid include hidden text, duplicate content, and off-site elements on pages.