There must be one and only one h1 heading on every web page, and that will usually be the title of the page/post. Use h2, h3, and beyond as headings and subheadings within the body of your text to break up large sections.
Organize headings and subheadings hierarchically, with headings first, followed by subheadings in order. All heading levels must be properly nested, following either a heading of the same level or a heading of the level immediately preceding it. (An h2 will nestle under h1, an h3 under h2, and on down.)
Subheadings (h2, h3, etc.) break articles into smaller, more specific sections. They give readers avenues into your content and make it more scannable.