If there are five or more navigation links and/or other content that comes before the main content of the page create an anchor link at the main content area of the page and insert a link that points to the named anchor.
There are potential problems such as conflicts when using both tabindex and skip navigation links and an IE bug that you should investigate before including a skip navigation link.
<a name="mcontent" id="mcontent"></a>
Place the skip navigation link anywhere near the top of the page. For example,
<a href="#mcontent"><img src="skipnav.gif" alt="skip page navigation" height="1px" width="1px"></a>