Practical Usability Methods in Website Design USABILITY THROUGHOUT THE DESIGN PROCESS
The basic stages of our website design are Planning, Analysis, Mockups and Prototypes, Production, Testing, Launch, and Maintenance. Several of these stages may involve phases of usability evaluation and redesign (especially with prototypes), and the stages are not meant to be viewed as strictly linear and non-overlapping. Following is a summary of these stages and some of the techniques we use to integrate usability into the process.68953
Planning
In the initial stage, a project plan is formulated with information about budget, schedule, necessary resources (e.g. software), and personnel who need to be involved. These are the constraints that apply to usability considerations at every subsequent stage, setting the framework for making necessary tradeoffs. At this point, a usability plan is created to clearly specify the target user population, their expected use of the website, and the type and depth of usability evaluation to be performed.
Analysis
In an initial design session with the client, requirements are determined with help from an interview form which identifies key issues to be specified. When users are accessible, straightforward interviewing and questionnaire approaches can be used to gather further user requirements.
Technical requirements must also be determined early, such as the need for special database, multimedia or security elements. Although somewhat orthogonal to usability, the available technologies can impose severe restrictions on interface design.
With requirements in hand, usage scenarios, user-modeling, and other forms of analysis can be conducted as needed. At this point, the structure of a site can be outlined, and specifications drawn up for the designers and producers.
Mockups and Prototypes
Simple sketching and mockup techniques can be used to quickly explore alternative visual designs and get client feedback [1]. Similarly, rough drafts and outlines of the textual information are created and functional prototypes for technical elements are built. These drafts and prototypes can then be evaluated using functional checklists (i.e. can they be implemented successfully), usability inspection checklists, task analysis, and with user testing and user feedback. Projects with larger sites and sites with complex interactivity will often need to continue this design cycle using semi-operational prototypes. Although there is no substitute for testing with real users, task analysis techniques will often identify interactivity problems in a more cost-effective fashion early in the development cycle.
Because of the high cost of later design changes, clear communication with the clients and users is essential at this stage. Mockups and prototypes serve well to clarify what are sometimes abstract design requirements, and every effort should be made to arrive at a final design by the end of this stage.
Production
As design documents and mockups are finalized, the producers of a website refer to sets of guidelines (for text, graphics, and interactivity) to develop the details of the design and transform that design into an implemented system.
Testing and Launch
Functional and user testing may occur throughout the production process, and meeting performance criteria determines when a website can finally be launched. Usability inspections and client feedback are also crucial to identifying final problems. We consider functional testing to be an essential aspect of usability since a website is not usable unless it works correctly and fulfills the needs of a user. Checklists of commonly-encountered problems can guide a functional or user test to quickly identify major concerns.
Maintenance
Site maintenance should be accounted for in the initial planning stage, but the exact nature of maintenance requirements can often change during the course of development. Website documentation and design guidelines are a useful output of the production process which are used as changes are made. Functional and usability checklists are also critical ways of ensuring that regular changes preserve the integrity of the design.