Wireframes
Wire framing a Website involves building a linear version of the site, with areas of the site blocked off in boxes - without graphic detail. It helps create visual hierarchy and spatial relationships with the various elements in the page.
Within this wireframe regions of content, navigation and graphic representation provides a real feel for how the information on your site connects is chunked and how the site flows. It keeps the "skin" or look and feel separate from the core elements of page layout. It enables you to pinpoint potential problems that might arise later on, once you've added content to the site.
Example Wireframe:
Wireframe at least the first two layers of your site, i.e. home page and secondary pages.