Taking enough time to plan your site properly might seem an obvious consideration, but it's also an important one.
Think carefully about what you want your pages to look like, what information you want include and where, and how you'd like visitors to navigate around.
At the very least, you probably ought to include a homepage with a rough overview of the site and your contact details.
Mapping things out in rough on paper will help.
What size would you like your headings and boxes to be? Do you want to include photos or other graphics? If you're creating more than one page, how should each part of the site relate and link to the others?
You may also want to focus on a particular theme or subject, such as your business, a pastime, or perhaps a sport.
Also, it's impossible to cook without the right ingredients, so make sure your raw materials are the right ones. Check that your computer supports the programmes you need to run - a basic text editor, a web browser, and maybe some kind of photo editing software such as Photoshop.
All these things should be considered at the planning stage. And investing a little time early in the process could save you a lot more time and hassle later.
Once you're satisfied with your preparation you'll need to familiarise yourself with a few things, starting with HTML.