One should avoid title capitalisation, such as A Very Fine Heading, and instead go for A very fine heading. Gratuitous capitalisation, or title case, often show a misunderstanding of – or a disregard for – orthographic conventions. We prefer what is known as sentence case, with a single initial capital to start headers.
When editing the documentation’s source, which is written in plain HTML, limit your line lengths to around 72 characters.
Some of us take this one step further and use what is called semantic linefeeds, which is a technique whereby the HTML source lines, which are not read by the public, are split at ‘natural breaks’ in the prose. In other words, sentences are split at natural breaks between clauses. Instead of fussing with the lines of each paragraph so that they all end near the right margin, linefeeds can be added anywhere that there is a break between ideas.
This can make diffs very easy to read when collaborating through git, but it is not something we enforce contributors to use.