They always have difficulty finding information, so they need support in the form of a strong sense of structure and place. Start your design with a good understanding of the structure of the information space and communicate this structure explicitly to the user. Provide a site map and let users know where they are and where they can go. Also, you will need a good search feature since even the best navigation support will never be enough. Don't mess with these colors since the ability to understand what links have been followed is one of the few navigational aides that is standard in most web browsers.
Consistency is key to teaching users what the link colors mean.
Outdated Information - Budget to hire a web gardener as part of your team. You need somebody to root out the weeds and replant the flowers as the website changes but most people would rather spend their time creating new content than on maintenance. In practice, maintenance is a cheap way of enhancing the content on your website since many old pages keep their relevance and should be linked into the new pages. Of course, some pages are better off being removed completely from the server after their expiration date. Traditional human factors guidelines indicate 10 seconds as the maximum response time before users lose interest.