This is just a quickie for now, I will elaborate further when I have more time. Even so, just by using the following list you will dramatically improve your sites rankings and traffic, the rest is up to your site =)

This list is written with Google in mind although you will see improvement in other search engines.

1. Get Google Analytics and Google's Webmaster Tools running with your site, this will provide you with loads of useful data while allowing you to control some aspects of how Google handles your site.

2. Do thorough keyword research using Google's External Keyword Tool, when using this be sure to set the region you want figures for and look at the Exact figures, not the Broad ones shown by default.

3. Use Google's Local Business Center to get your business shown in local search results.

4. Write quality content that will attract links while ensuring your keywords are present, no spamming!

5. Write sensible page titles that reflect the content of the page, again use your keywords here aswell as your brand name. For example;

6. Using a META Description tag is optional, they do not affect rankings but do offer control over the snippets shown within the search engines.

7. The META Keywords tag offers no ranking advantage.

8. Build quality links to your site from other websites relevant to your own. Using topic related forums and blogs is one good way to do this, be sure to participate and contribute instead of just spamming for links. Finding websites within your own industry with Guestbooks is another way to pick up some handy links aswell. When building links you want to have keywords in the link text (anchor text) where possible, just don't use the same link text over and over, change it up. For example;

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