In “Usability 101: Introduction to Usability” Jakob Nielsen describes the what, why, how, when, and where of web page usability.
Usability is a “quality attribute” that determines the ease of using user interfaces. There are 5 basic components that define usability: learnability, efficiency, memorability, errors, and satisfaction. When designing a web page, the designer wants to make a page that is easy to learn, highly efficient, memorable, free from errors, and pleasant to use. Additionally, the user must be able to do what they went there to do; if not, all of the above attributes are pointless.
If a website is not usable, the user will leave. That is the basis of why usability is important. In e-commerce, no one will buy a product he or she cannot find.
Observing users as they navigate your site is the best way to improve usability. The important thing is to shut up and watch and let them do the talking. It is easy to tell when they are having problems, or when they are easily navigating. All that you will need to do is write down their reactions, comments, and difficulties.
The best time to test is throughout the entire process. Test your old design and competitors’ designs. Make paper prototypes that will allow you to save time. You can make sure that the interface is usable before you do all the work associated with making a full-blown page. Make sure that users test it as early in the stage as possible.
You don’t need to set up a total testing site, just put someone in a room with you where there won’t be distractions, and you can easily do the test.
In the future, I will make sure that I test each web page myself using the accessibility tools provided in Microsoft Windows XP. I will also use my wife as at least one tester to make sure that it is easy to navigate and to use.