An introductory paragraph full of lots of interesting text, which goes on for a few lines to take up space. Plenty of space. Very interesting text. So interesting, you can’t wait to see:
Such excitement! Subheadings after headings. This must be a really interesting web page to require such exciting headings. We really ought to have another one, to finish things off.
There. Now this feels like a proper mock-up. You can really get the feeling of a full page outline, can’t you?