Throughout the planning, designing and building process you should document standards and methods in order to develop a comprehensive checklist. Once you have made a page selection then testing should involve all, or a combination of, automated, manual and user testing.
Selecting pages for testing
On large sites checking every page is not always possible. A representative selection of pages needs to be identified therefore. The home page is the obvious page to start along with other main content pages from the second and third levels. Pages with key functionality should also be looked at such as the search pages, forms, pages with multimedia and listings pages. Generally issues identified will probably be evident site wide.
Automated testing
Automated testing can be very useful when used in addition to manual testing.
Automated testing tools such as Wave, aDesigner and Deque Worldspace are developing and changing all the time just as access technology is. The key to testing with these tools is understanding which accessibility issues can and can not be tested automatically.
Automated checking tools are a valuable means of highlighting potential issues such as locating missing "alt" text (alternative text) and listing pages in the site where such issues exist. This is something that manual testing alone cannot do on large sites however, automated testing is far from comprehensive. Human judgement is needed for clarity and sense checking of text, assessing the navigation, and pinpointing if accessible alternatives are in place.
Learn more about automated testing.
Manual testing
Manual testing means essentially testing a website using various assistive technologies such as screen magnification software, screen readers and braille displays and text-based browsers. This will give an immediate and very clear indication as to whether your accessibility goals have been achieved.
Most access technology packages have demonstration versions that can be downloaded from the web. Some also have online versions such as the text-based browser Lynx. The testing abilities of the standard web browsers such as Internet Explorer, Navigator and Opera should not be underestimated. They are powerful tools for checking the accessibility of pages as they can be adjusted to simulate various outputs of web pages.
There is also a large amount of tools, usually working in combination with the most common browsers. They can be used to highlight issues in pages, enable or disable browser settings or check specific parts or features.
Learn more about manual testing.
User testing
Ultimately, a website will stand or fall on its ability to attract and retain people. It is therefore vital to research and incorporate feedback from groups of users throughout the design and build process. If done correctly, it is possibly one of the best ways you have to test whether you are meeting people's needs and expectations. The groups you use for testing and feedback can range from specific groups with disabilities, through to consultant specialists.
Learn more about user testing.