Divide your folders into pages, images and any other main group you may need. Within these folders may be subfolders. As an example, you may have a folder called images with sub-folders called headings and buttons. Finally, design the look and feel of the site. Just because it can be done, does not mean you should do it.
White space is good.
Limit the use of animation and flashing text. If you have animation, it should run once and stop. Does the site look good and work in both Netscape and Internet Explorer. Remember, plan and organize, so when you build your pages, you will have everything you need.