Search engine optimisation is now far more than putting some keywords into a page and mimicking them in your meta data. Search engines have brains and combine a whole heap of site tests in order to assess where your site should appear on the search results.
Most importantly, it is vital that the content in your page is correct and reflects the pages purpose, this is not just in the text but also, the images should be named accordingly to reinforce the content and ALT Tags used to aid the visually impaired user. A good example of this would be a product on an ecommerce site. The product has a brand, possibly a model and what it is. This text will no doubt be on the page but the search engines will check the pages images to see if it matches the content and so imagery should be named accordingly.

In this example the image should be named Dakine_101_Rucksack.jpg the underscores allow the search engine to see the text as separate words and therefore understands exactly what it is. The ALT Tag should read Daking 101 rucksack.
Approach – Assessing the site
A good place to start is to access the site. I use Domain Tools to get an initial overview of how the pages are scoring and the Alexa page rank gives you an idea of your website overall placement out of all the websites in the world (more detail on the Alexa site) I then move onto the SEO Browser located on the right hand side of the whois lookup on domain tools.

By clicking on here you will get to see how a search engine views the site and what the true content looks like. In the top right hand corner you will see a percentage score for the site. By clicking on the I button on the top left of the browser you will see a break down of the score and what needs improving in order to achieve 100%

The SEO Optimisation notes on this page are broken down into the following categories; Meta, General, Keywords, Composition, Links, Images and Terms. All are very important and getting everything right will result a massive shift in search engine placement.

Note: Achieving 100% on this assessment is all well and good and is quite easy to do but the score must reflect your initial copy, content or purpose for the website. Getting this wrong will not attract your target audience and even run the risk of being seen as a spam site.
As touched upon earlier search engines are also very conscious of accessibility for disabled visitors. The Images category in the SEO Browser reflects some possible issues such as alt tags (alternative text) missing and also images not having height and width attributes assigned within the html.
At this point I would move to the W3C (Web Standards) website and use there tools to check the page for accessibility and also for correct use of html. The Markup Validation Service will identify missing code (often accessibility issues) and also errors in the code. Again two identical sites one with errors and one without would affect the websites position on the search engine.

Using Google as a benchmark is always good as search usage figures of their competitors does not even come close to that of Google, as you can see using analytical software on any website. To begin with, installing Google toolbar to your web browser will allow you to see the Google page rank of every page you visit marked out of 10. This is not only useful in accessing your own page but also that of your competitors.

For far more detail on page ranks and how they are achieved you can also use the webmaster tools in your Google account. The webmaster tools are generated when your Google sitemap is submitted and pages are indexed on the Google database. This service provides various assessments broken down into the following categories, Overview, Settings, Diagnostics, Statistics, Links, Sitemaps and Tools.
This sitemap should not be confused with a sitemap page within a website. These pages are designed to ensure there are link trails throughout your site and do help the spiders navigate your entire site but are not used to index your site on a search engine.

Sitemaps in another session!!
Note: Similar sitemap submissions are necessary for other major search engines including yahoo and msn.
So… knowing what we now know and lets say we have applied all our changes to improve naming conventions, errors, accessibility etc, how do we climb the search engines?
I like to work backwards and reinforce what we have already achieved. At this point it’s good to know and assess where your existing traffic is coming from. This can be easily identified with Google analytics or AWStats. and allows you to identify the terms that users are searching for and arriving at the site. With this information, greater density of keywords and terms can be added further in the copy and stressed back through the meta data page title etc as identified with our earlier tools. Also it is useful to quickly identify keyword and term frequency, a useful site for this is LinkVendor words appearing a number of times within a page are not always used in the Meta keywords, description and title and as a search engine does not understand subject matter these words should be considered. Finally, and this is one of my favourites SEMRush formally known as seodigger. Pop your domain name in here and it will reveal loads of search terms, where you appear on Google for each term and the traffic they generate. SEMRush are now providing the same for adwords keyword terms.
It is also good practise to look at your Google Adwords and your Google organic traffic as a cost saving exercise for your Adwords account and also to identify terms to work into your natural traffic sources but that’s a whole other project.
Final Thought – All this is useless if you make a number of changes at the same time as you will not know which has worsened or improved your placement also unless you monitor your progress you have no means of knowing if it is working.
Useful Tools
www.domaintools.com
www.alexa.com
www.google.com
www.linkvendor.com
www.semrush.com
www.wholinks2me.com
Also available from my head.
Sitemaps, PPC Campaigns, Analytics, quality linking, usability,