Basic Rules of Web Copy
Whether you're writing copy for a commercial site, a blog post, or spamming people with a newsletter, at some point, you have to sit down and write some web copy. What separates good web copy from bad web copy, however, is that good web copy is easy to read and can be absorbed at a glance. The easier that the content is to read at a glance, the more likely it is that users will read the whole way through. There are several benefits to users reading your web copy from beginning to end:
1) Your message actually reaches them.
2) Consequently, it makes for better viral content.
3) They spend more time on your pages.
4) They become more likely to navigate to other pages.
Therefore, you might want to follow some basic web copy guidelines whenever you sit down to generate text-based content for your online media.
Use the Inverse Pyramid Style
This is the standard for most newspapers and magazines. Simply put, it means start with the most important information and work your way down. In other words, start with your conclusion, follow it up with your most important points, and so on. When the first paragraph states the purpose of the page or post, users can decide right away whether or not the page is of interest to them. Even though you want them to stay there as long as possible, if it is not clear what the page is about, they are likely to click away.
Layout
It is best that your pages/posts can be absorbed at a glance. At the same time, however, you want to avoid having a too much white space on the page. Consequently, 250-350 word articles are ideal. In general, however, pages/posts should not exceed 500 words. If they do, try to determine a way that they can be broken up into separate pages.
Write Short Paragraphs
When writing web copy, paragraphs should be no more than five lines. Generally, 2 to 4 sentences is a good length for a paragraph. When users can skim through a paragraph quickly, reading the entire page/article/post seems effortless. Consequently, there is a much higher likelihood that users read through to the end.
Concise Sentence Structure
In web copy, sentences need to be more than grammatically correct. They need to be concise. Even if they are grammatically correct, lengthy sentences can be difficult for users to follow. Consequently, sentences should not exceed 16-20 words in length.
Use Larger Fonts
Just like shorter paragraphs make content easier to read, so does a larger font. A 10 point font size might help you get more content onto one page, and into one screenshot, but it makes reading it more difficult. In general, a 12 to 14 point font is deal--depending on much content is on the page. If users have to strain their eyes, they will click away. Similarly, if reading the whole article seems like it's going to be a task, they will also navigate away.
Use Keywords... Gratuitously
Once you have state what the page or post is all about, keep on repeating it. If the page is about "PPC advertising," don't write "advertising." Search engine bots are (hopefully) crawling your site for keywords, and page content is one of several methods to search-engine-optimize your site. Now, this will not make for the most stylized content. It will still convey the same point to the user, however, and they will excuse the lack of style. After all, informative content is the most popular kind of text-based content online.