The Stanford Persuasive Technology Lab has compiled 10 guidelines for building the credibility of a website. The guidelines are based on 3 years of research that included more than 4,500 people.
Make verification easy
Use: Citations, references, source material, links to evidence.
Show that you’re real
Show the real people
Use: Images and text to convey trustworthiness.
Let people contact you
Make it easy for your customers to get in touch. Sites that went out of their way to make it easy for customers to get in touch, was seen as much more credible, than the ones forcing customers to go through a contact-form, or not providing any means of contact whatsoever.
This is a very easy way to boost your site’s credibility. Let your users know, that if anything goes wrong, they can get hold of you.
Like Don Norman said, Attractive things work better. People quickly evaluate a site by visual design alone. Your site will gain credibility if its designed to what is proper for the audience. The visual design should match the site’s purpose. Using the layout of a banking website for a Woman’s fashion site, will probably not yield the best results in terms of credibility.
Pay attention to: Layout, typography, images, consistency.
Usability and usefulness
Sites that are updated or reviewed recently are seen as more credible. If people come to your site and find that the last update was 5 years ago, they will think your site has been deserted. If you haven’t got updates to present, then at least show that you haven’t forgot about it – that you’ve reviewed your site recently.
Restrain from promotional content
If possible, try to avoid ads or at least remember to clearly state when content is sponsored and when it is not. Every time you disturb your users with pop-up ads or attention-grabbing ads, you are loosing credibility.
Make your communication, both in graphically and in writing, clear, direct, and sincere.
Use: Clear, direct, and sincere writing style.
Typos and broken links hurt your website’s credibility more than you think. All the things, no matter how small they are, that either gets in the way of achieving a goal or make the user spend more precious brain energy than necessary hurts your site’s credibility. Also – keep your site up and running.