Not reading through 5 pages worth, so I'm sure my comments have been doubled by other people.
1) Play it. Hard to learn something without playing it and studying without playing is fool's gold.
2) At 1100-1200 you're unlikely to get deep theory in the open Sicilian so I would focus on a setup that can be reliably reached for most games and works decently against both kingside castling and queenside castling. The dragon is actually really good for this as the main problem of the dragon (the Yugoslav) is not going to be played or if it is, is not going to be played accurately at that level. Otherwise one of the French Sicilians (Taimanov-Kan) gives you the approach of trying to get an improved version of the French defense.
3) Learn ways to combat the intermediate friendly antis mainly the Alapin and Morra. These will be played against you and likely more accurately than someone attempting an open.
What you shouldn't do is memorize reams of open Sicilian theory that you won't play until significantly stronger.
I don't know why you recommend this stuff. There is no point messing around with move orders to enter the Accelerated Dragon. It's not that big of a deal to learn the Rossolimo compared to any of the lines in the other move orders.
++Move order is rather important, and if you can avoid the Rossolimo, that's one less variation you don't have to learn. And if learning one less variation makes games even that much easier, why learn it if you don't have to?
You recommend all these weird, offbeat lines all for the sake of "avoiding theory". As if it's so important to "avoid theory" compared to actually learning something and playing a good opening. It happens a lot that lower level players try to play some offbeat line against a higher level player to try to "avoid theory" and then just end up with a terrible position. Also because if you are constantly avoiding learning anything then you are not even going to understand the offbeat line that you play. It's not worth it to avoid main lines in order to just play a bad position where you get yourself into a mess. Sooner or later players will start punishing you for it.
++ See below.
They said they already thought about whether they should play the sicilian before making the post and already decided to do so. The original post was not asking anyone to tell them which opening to play.
++ I have decided that there is a small chance that you are illiterate. I quoted the original poster, explained my reasoning, and still you come after me about something that is simply incorrect.
Avoiding mainline theory got me from 1000 to 1500, stopped working, so I learned theory over the course of a few months, started playing longform theory and went from 1500 to ~1730 peak in literally two days. Meanwhile, an OTB friend of mine (+= OTB rapid and blitz record against me, similar time playing chess overall) only plays mainline theory and is hardstuck around 1100. I fully expect them to catch up to very quickly if they ever make it past 1400. I never recommend "avoiding theory" in the way that your post below does, as that is INCREDIBLY stupid. I recommend "avoiding theory" by not playing mainlines. For example, between like 900-1300, I would never recommend playing the Italian as White or 1... e5 non-Petrov's openings as Black because everybody plays the Fried Liver, and so a lot of players in that range know Knight Attack counterplay like Polerio, Traxler, or Ulvestaad. I played a match at 1100 blitz where we went 8 moves deep into Polerio Bishop Check Line Bogojubilov theory, but I didn't understand anything about the resulting position and lost in 15 moves. Meanwhile, once I realized everybody did the exact same thing, I started playing simple Petrov's, Alekhine's or Modern theory against 1. e4 (all of which I understood) and my ELO skyrocketed. Then, I switched back to playing mainline Italian, Scotch, and Spanish theory once I hit a plateau around 1500 and again, instant results. Mainline theory has its place, and that place is for players 1500 and higher, where half a point of material genuinely means something half the time and endgame conversions are inevitable.