1. Mobile Compatibility

As more and more people use their mobile phones to access the Internet, creating a mobile optimized website has become a necessity.

The first step is to check how your existing website appears on mobile. You can use Google mobile site tester to find this out. If your website cannot currently be accessed on mobile, you can create a mobile version of your website for free with the help of web-based mobile website builders.

2. Accessible to All Users

A user-friendly website should also be accessible to everyone including blind, disabled or the elderly. These users typically use screen-readers to access the Internet. The website accessibility guidelines highlights simple web design techniques that can be applied to make sure your website can be accessed easily on-screen readers, making your website available to a larger audience.

3. Well Planned Information Architecture

How information is organised and presented on your website is vital for good usability. However, it is often neglected. It has become even more important today as websites offer a wide range of information and resources to attract their target market. Plan your website sections and categories carefully and present information in a way that it is easy for users to find. Always think from the perspective of your users. This is particularly important if you offer a lot of content on your company's website.

4. Well-Formatted Content That Is Easy to Scan

The average Internet user skims through the content on a web page instead of reading each and every word from top to down. Users tend to scan through key parts of the page quickly to determine if it is relevant to their needs.

It is important to format your content with this in mind. Correct use of headings, sub-headings, paragraphs, bullets or lists help to break up text, making it easy for readers to scan.

5. Fast Load Times

Nothing is more annoying for website visitors than a website that takes long to load. In fact, slow speed is one of the main reasons why visitors leave a website. Making sure your website loads within 4 to 6 seconds is important for good usability. It also affects your search engine ranking.

You can use free tool such as Pingdom to test the speed of your website and to get suggestion on what you can do to improve your speed.

I have found third-party website plugins and widgets including website tracking, social media, to be one of the most common factors that affects website speed. Try to limit their use and only use the ones that are absolutely necessary.

It is also one of the main reasons visitors leave your site. Customer expectations have changed significantly in recent years. A typical customer will only wait for a few seconds for your page to load, after which they will most likely navigate away to a competitor's site never to visit again.

6. Browser Consistency

Browser compatibility can be easily overlooked. Even the websites of some of the most reputable companies suffer from this problem due to neglect. This is bad for branding and has a negative affect on website usability.

Although modern browsers have evolved and become more efficient, some inconsistencies still exist in how a website is interpreted by different browsers. It is important to ensure your website appears and behaves consistently across all major browsers such as Chrome, Internet Explorer, Firefox, Safari and Opera. Simple things like this set a professionally designed website apart from the rest.

7. Effective Navigation

Good navigation is one of the most important aspects of website usability. Simple HTML or JavaScript menus tend to work best and appear consistent on all browsers and platforms.

It is equally important for the navigation to be clutter-free. Try to limit the number of menu items as far as possible. A drop-down menu or sub-navigation may work better on large site with many sections and pages.

Advancement in DHTML, and JavaScript libraries such as Motools and Ajax also opened the doors to many new possibilities for creating innovative navigation systems. Take a look at Mashable's example below.

There is more to navigation than menu. Here are some other aspects to consider:

• Good search feature.
• Multiple ways to explore content e.g. top 10, most rates, most popular, etc.
• Custom 404 Page.
• Good Internal Linking
• Informative header and footer

8. Good Error Handling

Good error handling and description on-screen messages are very important for good usability. However it is often overlooked. Correct handling of errors at a code level ensures the website is robust and free from bugs. Displaying the right error message improves the user experience and overall usability.

9. Valid Mark-Up & Clean Code

A website that adheres to the relevant web design best practices and standards is often more robust and dependable. It also ensures the website will load faster and appear consistent across browsers and devices. It also makes it easier to locate problems and troubleshoot if the need arises.

More information and mark-up validation tools can be found on W3C's website.

10. Contrasting Colour Scheme

The right contrast between the background of the website and content is one of the most basic yet most important web design principles that should never be overlooked. Good contrast between background and text e.g. black text on a white background makes your content legible and easy to read. Lack of contrast, on the other hand, makes it very difficult for visitors to read your content.

11. Usable Forms

Forms are a very important element on business websites. They allow users to interact with the site. Forms are also very useful for generating leads for a business.

To get the most out of your site, it is important to ensure the forms are easy to use and accessible to everyone.

Here are some tips:

• Use correct labels for all fields
• Follow good form design principles
• Try to keep the number of fields to a minimum
• Offer tooltips and suggestions
• Display on-screen message on completion
• Use correct validation