1. Setting Up. Whether you are designing your own site or gathering information for a designer/developer it is a good idea to set up a special folder for your website. Within that folder have folders labeled "working files" (for the content and any images and graphics that you are creating), "images" (where you will place the finished graphics and images), and other special folders. I find that if I keep everything well organized, adding, expanding and moving the site becomes much easier.
2. Pick an authoring program. If you are designing your own site, you may use HTML (straightforward coding that is easy to learn, but has design limitations) or you may decide to use a WYSIWYG (What You See Is What You Get) program. Examples are: