Not general headings such as Introduction, Our Products, History. They are hopelessly vague. And don't try to be too clever. Write links that work like headings. Capitalize on your audience's intuitive response to highlighted words.
Some people scan Web pages by jumping from one link to another.
Adapt articles for easy scanning. Highlight significant phrases in bold or another color. Use bullet points. The ideal length for a bulleted list is 3-5 items. You may need to combine several items into one or break up a long list into several smaller ones.