Before writing documents writer should know (or have some kind of idea of) subdirectories where different files are going to be located. Writer should also think how text is to be divided into HTML files, e.g. each chapter is separate file and has links to previous chapter, next chapter and table of contents. If writer don't know organization of files it is very difficult to create links to other documents and pictures. For example it could be usefull to have pictures in their own subdirectory.