If you want to write a website that will "Generate Sales" you need to do a few things more than simple website design.
First of all: If you just put a website online it will do nothing. It will not be indexed it, it will not generate sales and it will just sit there like a Tesco's in a forest.
If you want to be found online, here's what you need to do
When you write your website keep in mind the keywords that potential customers will type in to find you. Make your website title and URL include these keywords if possible. Here's a great example - http://CorkWebsiteDesign.net You will see it's target market is website design within the Cork area.
You will notice all the images have been saved as to include the keywords "Cork Website Design" The reason we do this is so your site will also be shown in the results "images" for your keyword's.
Make sure you have all titles and header including your keyword's. Also make sure you get your keyword ratio for your site text approximately at 5% of words being keywords. This really helps the search engines to understand what your website design is all about.
In the example site above you will notice that the long tail keyword "Cork Website Design" is being used as the Title and the URL and has a ratio of ruffly 5% within the text. As expected this is a very well optimized site, which is not unexpected concidering it is a website design companies homepage.
Did you notice how that website design incorporates regionalism By adding a location to the keyword you instantly remove the vast amount of competing websites as your competition. By narrowing your niche you reduce your market, so make sure you target exactly the people you need to.
The next trick is "back linking," and as you will find, no matter how good your website it must first must be found by Google and the other SERF's before it can be ranked. Your website will be ranked according to how accurately you have performed your SEO and the amount of sites that are linking to yours. The main backlinking strategy I know of is article writing. I encourage you learn more about back linking.
These are just a few of the techniques we use but you can inquire if you would like help with anything else SEO related