The first thing you can do to make absolutely certain that your pages are given the best fighting chance at conformance is to begin with all the required and structural elements that are needed before you begin to add text and other content.
Ironically, it's only been in hindsight that the majority of people working on websites have improved upon the way they use markup. The Web was in such a state of evolutionary, rapid growth that new elements and features were being added to browsers and HTML all the time. Many of these features made it into the actual specifications, but many did not. What's more, elements of HTML pages that should have been included from the beginning have often been left out, even by professionals.
How is this possible, you might wonder? Well, the primary piece of software used to interpret HTML is the desktop web browser. These browsers have a long history of forgiving errors. Of course, they also have a long history of introducing errors! Browsers have been both the blessing and the curse of the Web because they have allowed for innovation but often spent more time adding fun features rather than basic support for the languages they are meant to support. As a result, the Web is a mishmash of HTML use most of it not conforming or valid and, in light of this tutorial's discussion, many times authored without the basic structural components required by the language.
A movement is afoot to bring better standards to browsers, to the tools that people use to develop websites, and to those of us interested in creating pages that not only work, but work well, regardless of whether our goals are personal or professional.
In this tutorial, you learn to create a template that will serve as the foundation for everything you do in this tutorial. This template will contain all the necessary and helpful technical and structural bits that form the basis of a document that will conform and validate, too.