I have tried to put the steps in an approximate order of priority, but these should not be viewed as discrete unrelated tasks.
If there is one thing that is worse than not having a website, it is having a bad website which damages your reputation.
In fact there are so many people or companies doing websites badly that there is even a website and book on that very subject.
I have already written a review of the books: Son of Webpages that Suck, and Web Sites that Work.
Your website should be designed with your target audience in mind.
Factors that should be considered include: the target age group; skill level and interests.