The overall topic of web design, from conception through to going live and publishing the site is just too big with far too many variables involved to offer a definitive guide.
Getting started is a matter of obtaining some useful software, having a topic that you know enough about and are passionate enough about to warrant spending the time to produce a site based on it, playing with your chosen layout and design, choosing colour schemes, creating graphics and/or taking relevant photographs and so on.
Your best bet is to start off with an idea along the lines of a hobby or other special interest you may have that you'd like to share with others. Think about how you might like to present this information to others, how our pages could be laid out, how they could logically link from one to another. Take a look at other sites you have found that you like and make notes of what it is you like about them. Don't steal ideas, but learn from what you like and discard what you don't like.
When you first start out it can help to draw with pen and paper and sketch out your ideas. Transposing a firm concept into a web page is far easier than fooling around with a general idea and o real direction. Planning and preparation is everything and it actually cuts down your end workload and learning curve to have a very strong concept in mind.
Your ISP will probably provide you with some free web space which you cam use to practise with. You can get a pretty good WYSIWYG (What You See Is What You Get) editor free but for the time to download it from this link click here
It was originally written for Linux but has been ported over to Windows and it works well without costing you an arm and a leg. If you want to buy software, you could do far worse than NetObjects Fusion to begin with, which is about a third of the cost of Dreamweaver but far easier to use overall for most beginners.
Try the excellent WebMonkey and W3Schools sites click here and click here respectively, for more web based tutorials than you can shake a stick at. It's pointless suggesting one book on the subject when so many free articles and tutorials are available to you.
Basically, you need an image editor, a web authoring program of one type or another, the ability to use them and a good idea for a site. If you couple that with some of your free time you’re off to a good start.
Feel free to ask about specifics, but a full tutorial on designing a site is an all but impossible task for this forum. There just isn't enough space or time to post something like that.