where do You start In Seo ?

Well Im actually got a client and he wants me to do seo and everything but I dont know where to begin; anyone know where I should start ?

thanks guys for the help and comments

Description and Keywords meta tags are the best place to start, then meta tags in general.

Insert some keyword into content and title.
give some backlinks for your client

Start with good, valid markup. Use headings (<h1>, <h2>, <h3>) with a good amount of keywords in them.

Nice ideas guys, it helped me too. Thanx.

Start with the site's content. Quality link building thru forum posting, social bookmarking, press releases, etc. would help you a lot in SEO. If you want to increase your PR, focus more on organic / natural links and having links on high PR sites as well as directories. Submit to as many directories (with high PR) as you can for better results

Decide what keywords you want to optimize the site for and then include these keywords in the page title and page content. Make use of H1, H2 etc plus the <strong> tag on phrases containing or related to the keywords.

Don't worry too much about Meta tags. You can include the keywords meta tag but hardly any of the search engines pay much attention to it any more. The only meta tag I would really bother with is the description meta tag as snippets rely on it under some circumstances.

Make sure you validate the site with Google Webmaster Tools and submit a sitemap.

Then see about creating some good quality, keyworded backlinks on relevant sites. A little social bookmarking would probably help too.

Hope this helps

Also make blog comments but make sure you read the post and make a well informed blog comment

Make sure your source contains main content before navigations and extra stuff. Like:

As mentioned, start first with well structured xhtml, good use of keywords/phrases in <h#> tags and also good <p> content. Also make sure to change the title of the page to match what is on the site.