It is critically important to know how your site is being used. Your web site host probably provides you with free web metric software, but if not…
Google Analytics is free and easy to use. You can set up on your site literally in a matter of minutes. Once installed, you can login to your online account and see real-time metrics about how your site is being used. There you will be able to see all kinds of critical information, including:
Visitors (visits, unique visitors, geographic distribution, time on your site)
Traffic Sources (referring web sites, keywords)
Content (page views, top landing page, top exit page)
While Google Analytics is the most widely known, there are some other options you may want to look at including Clicky amd Piwik, an open source and non-proprietary alternative to Google Analytics. WordPress also has a plugin for stats.
Based on this information, you will almost certainly want to make adjustments to your site. You may want to refine your meta keywords or revise the navigation and structure of your site. You will learn how people are entering your site and where they are leaving it. You will also see what pages are being heavily used and which ones aren’t. Remember you want your web site to be the most effective tool possible and have the greatest impact on your audience. Your site is not a static entity, that once designed and launched, you will never have to think about again. Your site will always be a work in progress and you will need to refine it again and again over time.