I am really love this beginner's guide - Dos and don'ts posted by Stoney deGeyter on Search Engine guide.

Many SEO newbies, or new businesses starting out online, come to SEO blogs such as this looking for some quick and easy solution that will vault them to the top in the results. Unfortunately, there are very few hard and fast rules in SEO, and no step by step solutions that, if implemented, guarantees you top search engine rankings. If there were, then it would quickly become obsolete because everybody would be doing it.

Instead, SEO is more of a set of guidelines that can be implemented in a way that allows for individual site customization. Most of it is fluid based on each site's needs for their audience. However within that there are also some basic dos and don'ts that need to be adhered to.

SEO Dos:

Customize your title tags. Each page should have a title unique to that page alone.
Research your keywords thoroughly. You really cannot start optimizing until you have researched out your keywords and know how the optimization will play out.
Use keyword relevant filenames for each web page. If the page is about women's brown boots then your file name should be womens-brown-boots Such as: yourdoman.com/womens-brown-boots.html.

Organize your directory structure. Don't throw all your pages into the root folder and don't use too many directories/sub directories. Keep it simple yet organized.
Plan out your internal links. Develop your navigation effectively, implement no follows sparingly, link content to other pages liberally and use absolute links.
Use content effectively. Make sure your content does the job of selling to your visitors but is also keyword rich. Don't go overboard on keyword usage, but only as it functions best for the visitors.

SEO Don'ts:




Don't junk up your code. Get rid of junk code such as on-page styles, JavaScripts and excessive tables. Keep your code lean and clean and validate if at all possible.

Don't add a bunch of junk links to the bottom of your pages. Footer links are great, but don't just add junk links to pages that serve no value to your visitors strictly for the SEO benefit.

Don't settle for stock content. Take the time to develop custom content for your site. Don't use manufacture descriptions unless you add your own descriptive content as well.

Don't junk up your URLs. Keep your URLs clean and tidy without a lot of excess variables or session IDs.

These are just a few decent starting points for beginners in what they should and should not do with their site pages. Implementing these few tips won't suddenly shoot your site to the top of the search results, but it can begin the process of making your site much more search engine friendly and in a better place to be noticed by the engines.
If you want to know more go to http://www.searchengineguide.com/