What are all the techniques we want to learn for becoming SEO Expert?

Which is best guide for learning SEO (Search Engine Optimization) ?

Give some links for learning advanced techniques with free of cost?

hello friend..
well If you want to become a SEO expert.First you have to learn what Is Search engine and how it works…?after that only you can understand that what Is Going to be done in SEO work.SEO is The way to increase your websites traffic – Your business goals – leads.to boost up your websites ranking in various search engines like google,yahoo,MSN and other more than 365 search engines.SEO is very deep field my friend If you want to learn SEO you have to be a great reader.i am giving you some best sites references for learning SEO.They will provide you E-book too for learning SEO.this is a growing field in IT.If you become a SEO expert you can develop a great career in this field.
basically SEO is departed in Two main parts :-
On page SEO
Off page SEO

But If you want to learn SEO from Its basics refer sites given by me below and read all details given by them.It was nice to help you friend.Even If you want more information let me know i will surely help you.Thank you.Have a nice day.