Conducting a heuristic evaluation can be a cost effective and relatively quick way to asses the usability of your site. They can be conducted by a usability expert or, failing that, you can apply sets of tried and tested heuristics yourself. The most well known set of heuristics are Jakob Nielsen’s:
Visibility of system status:
The system should always keep users informed about what is going on, through appropriate feedback within reasonable time.
Match between system and the real world:
The system should speak the users’ language, with words, phrases and concepts familiar to the user, rather than system-oriented terms. Follow real-world conventions, making information appear in a natural and logical order.
User control and freedom:
Users often choose system functions by mistake and will need a clearly marked “emergency exit” to leave the unwanted state without having to go through an extended dialogue. Support undo and redo.
Consistency and standards:
Users should not have to wonder whether different words, situations, or actions mean the same thing. Follow platform conventions.
Even better than good error messages is a careful design which prevents a problem from occurring in the first place. Either eliminate error-prone conditions or check for them and present users with a confirmation option before they commit to the action.
Recognition rather than recall:
Minimize the user’s memory load by making objects, actions, and options visible. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate.
Flexibility and efficiency of use:
Accelerators—unseen by the novice user—may often speed up the interaction for the expert user such that the system can cater to both inexperienced and experienced users. Allow users to tailor frequent actions.
Aesthetic and minimalist design:
Dialogues should not contain information which is irrelevant or rarely needed. Every extra unit of information in a dialogue competes with the relevant units of information and diminishes their relative visibility.
Help users recognize, diagnose, and recover from errors:
Error messages should be expressed in plain language (no codes), precisely indicate the problem, and constructively suggest a solution.
Help and documentation:
Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, focused on the user’s task, list concrete steps to be carried out, and not be too large.
Another good resource is Userfocus, who have a useful Excel spreadsheet containing a list of recognised usability guidelines. It presents a series of statements about your website against which you are asked to score points on a sliding scale. The points are collated and displayed in a neat visual which illustrates the usability of your site against their specific guidelines.
A heuristic evaluation should not replace user testing, and should not be confused with it either. The evaluation is more of a sanity check. And as with everything there’s always going to be an edge case, whereby applying one of the heuristics may have a negative effect on the user experience.
The simple fact of the matter is that UX without actual user testing is not UX. So while you will rarely do any harm by applying simple tried and tested heuristics, you will never understand your users without user testing. There’s a fantastic article by Hoa Loranger on this very subject, and it should be given to every company executive who really wants to build UX into their process but is reluctant to cough up for user testing.