I I would like to learn Sicilian Defense after playing Scandinavian for months with satisfaction, but I'm more attracted by Sicilian. My favourite variation is the Najdorf, but I know that I can't force my opponent to play this variation, so, exactly, what other lines have I to learn against white choices to face the Sicilian? What is the best way to learn this defense which is full of variations and complications? I would like to learn it gradually in order to play it in tournament next year or next months.

Eesh. The Open Sicilian (1. e4 c5 2. Nf3 d6 in your case 3. d4 cxd4 4. Nxd4) is probably the most theory-heavy opening in chess, and a complete 180 turn from the Scandanavian.

Although it will not solve any of life's problems, Wikipedia is a good source of free, easy to find, and understandable explanation of basic variations and ideas. Sicilian Defence - Wikipedia, the free encyclopedia is the section on the Sicilian.

As for major deviations, White can play different second moves, like 2. d4, 2. f4, 2. c3, and 2. Nc3. A common third move for White instead of d4 (in the Open Sicilian) is 3. Bb5.

Word of advice: Decline the Smith-Morra Gambit (1. e4 c5 2. d4 cxd4 3. c3) at first. If you accept it with 3.... dxc3 4. Nxc3, you're just giving white what he wants. Until you have a lot of time to study how to play it in depth, you're better off just declining with 3. ... Nf6 4. e5 Nd5 and go from there. Much less theory to memorize, and you're taking white out of his preferred line.

--Fromper

GM Dorian Rogozenko has a book named "Anti-Sicilians", well i think there you'll find what white choices you have to face with...if you want the najdorf, study bobby fischer..he's a genius.

My favorite way to study an opening is to start playing it online and in blitz. Then as you become associated with its problems, hit the books. When you start testing it out you'll probably notice that you see a LOT of altrenatives on moves 2 and 3 (smith-morra, 2.c3, Closed Sicilian, grand prix attack, 3.Bb5+) - you may want to devote as much as 70-80% of your time just working on these.

The system of study could be to play 100 games of the Opening particularly from good GM games. Chesslive.de is a good source to play over games.

Very true. I am currently studying the Exchange Ruy, and I've gotten to 1.e4 e5 2.Nf3 Nc6 3.Bb5 only in 2 games out of 10 to 15. Quite frustrating.