First, identify the most important pieces of text on the page. This includes
Then check these texts for
There are software tools for such checking. However, such tools cannot replace human judgement and analysis, by you or others. If possible, ask other people’s help to evaluate your texts and try to learn from their comments. If you think that your text is crystal clear and your friend says that it is confusing, the odds are that he is right. Other people’s comments help you make specific corrections, but more importantly, they can help you to see your typical mistakes and avoid them.
The general idea is to use as simple and concrete language as possible. Therefore, the goal depends on the purpose of the page. If it contains instructions on voting in a general election, it should be very simple and specific, even at the cost of looking na´ve to some. If it explains advanced quantum electrodynamics, it needs to use difficult and abstract concepts and special notations. As a rule of thumb, there is always room for improvement. Find, read, and apply some style guides for the language you are writing in. You will notice that there is always something new to learn in writing simply and understandably; the important thing is to get started.
In particular, watch out for the following expressions:
Experts always overestimate the need for using special terms and phrases. They are accustomed to using them when writing and speaking to colleagues, so they will keep using them when trying to address a wider audience. You may need to be less exact in order to be more understandable, but often it’s just a matter of choice between common words and jargon. You probably recognize this in texts that are outside your expertise. If you do not work in the area of medicine, you realize that “myocardial infarction” is unnecessarily complicated language; it means “heart attack.” The crucial thing is whether you can see how much you and your colleagues use jargon that creates serious accessibility problems.
Use simple sentences. On some pages, you may need many technical terms, and you may need to imply that readers have university level education. This does not mean that you should use difficult sentence structures. On the contrary, when the vocabulary and the ideas are complex, aim at simplicity of language to reduce the difficulty of understanding. As a rule of thumb, sentences longer than 20 words tend to be difficult to many just because of their length. Preferably, make most sentences 10 to 15 words long.
Avoid ambiguities and possibilities of misunderstanding. This is often even more important than being understandable! If your text is difficult, the reader can re-read it and seek help to find its meaning. If your text is superficially easy and simple but potentially misleading, it will be misunderstood. Ask yourself: could someone really get a completely wrong idea of what I mean, if he really tried? If the answer is yes, many people will misunderstand the text without even trying.
The ambiguity problem is especially important when checking navigational links. Their texts need to be rather short, and authors often make them too short and just vaguely suggestive rather than clear. If a set of navigation links contains the word “Index,” how is the reader supposed to know what index it refers to? “Site index” is better. The link texts should be understandable to a person with no prior information about the site. He should be able to classify his problem or question into one of the categories described by the links. The common problem is that the link texts reflect the author’s or the organization’s way of thinking rather than user view.
Of course, you can apply such checking to all text on a page. The formulation of rule 1 is just realism: you probably don’t have enough time for full checking. Moreover, some parts of the textual content are far more important than the rest. However, for a page that does not contain any substantial amount of special or rare words, it is usually quite feasible to run a complete spell check.