Giving Shape to the Text
Having targeted your pages it's time to (re)write your content. If you're revamping existing content look at the way it's laid out - is it just one chunk of rambling text or does it have any structure to it. The latter is much preferable as long as it's correctly broken down. Look at how it relates to the keyword phrase you've targeted the page for.
Using Headers Naturally
Whether rewritten or new, if the text is properly relevant then it should be natural to start the page with a header that contains, or is closely related to, the main keyword phrase. The first few paragraphs should reflect this subject and describe your site's connection to it, whether it's a product, service, idea or general concept. If there are natural secondary subjects or more detailed discussions then these should have secondary headers. Itemised objects should be in lists.
Write for the User
Note that this approach is a natural one for the user - most people find reading a screen harder than reading a book or magazine / brochure, and unless they are reading for pleasure they have a shorter attention span because of it. Good use of headings, keeping sentences and paragraphs relatively short and to the point helps them absorb your message. The same approach also works well for the search engines.
Don't be a Bore
What you shouldn't do is repeat the main keyword phrase deliberately. Doing that is likely to make the text sound stilted. Write as naturally as possible and try to use related phrases to your main one. This approach will tend to automatically use the main phrase sufficiently and have it reinforced by related words. If there are related secondary keyword phrases then they can usually be slotted in naturally alongside the main one.
2. Targeting your pages < - Tutorials - > 4. Formatting your text