Where do you start with a brand new web site? What is it that you want to do with it? Believe it or not, the internet is mainly all about words. You may use it to view videos or download music, but even for these you search for words.
This is where you need to start when considering your web site. What do you want to say to your audience, and what is that audience? Ultimately a web site is for the purpose of getting a message across, whether it be nothing more than the fact of your existence and availability as a business or other organisation.
So, before considering how it should look or what it should do, you should always consider the content: the words, images, ideas that you wish to convey to your target audience. Design is very important, but it still plays a supporting role to the actual content, so start with the content; all of it before considering how you want to package it.
When you have done this you will find that the message gets the priority that it deserves once you get to the design phase of your web design project.