Define website structure (tree of files & maybe subfolders). There are two tough things to do with the client. The first is get him to articulate or to work with you to create the tree structure of the site. I've used wrpTreeForm to build into my software the ability to interactively manipulate the tree while discussing it with the client. This APL utility is very easy to use and is available as a free download from Bill Parke's web site.
Some APL developers are successfully using a far more sophisticated OCX control called TLIST, but Bill's APL utility is all I need for now.