You might be best starting off by doing some research. Look around the internet and get ideas by looking at the sites of other people. Some of the best to look at might be official sites of big companies because they pay a lot of money for people to design their sites so they should be pretty good. Once you know what you want it to look like you need to have the technical ability to make your page, this isn't very hard and is what the rest of the guide is for. One thing to bear in mind if your site gets quite large with lots of pages is how easy is it to find information.
Many sites are like mazes and many people just give in before they find what they're looking for.
This is one element where design is very important. You have to think about what information people will want to get from your site and then making it easy to find. It is very easy to avoid making maze like web pages with just a little thought. One of the most annoying things about making a web site is that HTML keeps on improving and getting new features but these new features do not work on older browsers. You have to make a compromise.