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a) Bankroll Management
b) Understanding how much to bet at various levels/stages of a tournament
c) Patience
d) Tilt-control
e) Putting people on hand ranges (and taking notes - specifically w/regulars)
f) Understanding when to open up your hand range (but this could be lumped in with 'b' above)
g) Trying to finish in the money (even folding a premium hand just to make it)
i) Keeping things simple at first, and adding things later
With 'Bankroll Management', depending on what game you're playing, it's best to play with 100 buy-ins. For example, if you have $50, it's best not to play in a $4.10 tournament, b/c you basically have 12 buy-ins which is playing with scared money. The swings in poker can be quite extreme, so it's best to go in where you can play comfortably.
If I'm playing at any Sit & Go NLHE tournament with seats of 6/9/18/27/45 or 90 players, I think 100 buy-ins is best. But if I'm playing in the 180-seat tournaments (FullTilt or PokerStars), I would ideally stick with 200 buy-ins b/c of the cruel swings. Some people believe that 30 buy-ins is good enough, and I would only tend to agree with that if it's another game besides NLHE - like Omaha - but you're putting yourself in a dire situation where you MUST run well. Even the grinders go on major downswings, and have days where they drop tons of buy-ins.
Here are a couple of useful links on Bankroll Management -
The most useful book (for me) on understanding how much to bet at various levels of any S&G tournament would easily be 'Sit 'N Go Strategy' by Collin Moshman. I hadn't read it until I'd been playing for a few years, and after putting it down, I was kicking myself for not getting it years before. Cash games are a completely different beast altogether, so if you're going that route (not an easy route), get something else. For someone who knows very little about poker, I suppose that Doyle Brunson's Super System I & II are okay, but the chapter on NLHE is VERY outdated (the chapters on the other games are fine though). You'd get yourself in a whole heap of trouble following the NLHE chapter for S&Gs (on par with those only gathering knowledge from watching HSP on TV and going out to conquer the world Tom Dwan/Dario Minieri style).
Being patient is HUGE. Remember that even though the same player keeps shoving on you, stealing your blinds (even in the later stages of a tournament), and you can't call b/c your hand stinks, wait... I'm at the point these days, that it's okay, as long as I still have 3 BB left (one last bullet in the chamber).
People tend to give up when they're down to their last 6-10 BBs, but never give up. I've come back on won a number of S&Gs when I was down to 3 BBs. If you're lucky enough to double-up once of twice (depending how much money is in the pot), you're back in the game (and the other player is probably on TILT and ready to donk off his/her money).
I've studied 'The Eightfold Path To Poker Enlightenment' at 'DeucesCracked.com' (under the poker videos section), and I'd highly recommend it to anyone (literally everyone) who has problems mastering 'Tilt Control'. It's easy to understand, and a very useful tool.
If you're playing everyday, and you recognize some of the other players (regulars), I'd implore you to make use of the 'notes' option. Gather whatever information that you can on the player and his/her tendencies. I'd suggest giving them a ranking (poor/fair/good/excellent or tight/aggressive/maniac/donk etc), and maybe write down the type of hands (range) that they play with. It could be a very helpful tool. Most regulars that I know use a HU display, but I'm not crazy about them.
Because you're new to poker, you're likely going to meet other people who'll recommend such and such sites, where people will tell you that in order to be a serious player, you MUST use a HU display, and Turbo Ninja, using an X-Box controller, playing 15-20 tables at a time, making sick rake-back... That's fine, if you're damn good. But keep things simple and add only if you're comfortable enough to do so. I added too many things trying to get better, and all I did was lose my shirt trying to keep up with all of it.
I could barely keep up with two tables when I first started, and now, adding additional tables over time, I can play 10 tables very comfortably (provided that I'm using the 'stacking' feature at PokerStars). I've played 20 tables at once a few times, but that's just not for me (mind goes numb by the end of a 2-hour session). Playing multiple tables has its advantages, specifically if I get sucked-out on at one table, I still have enough games going on at once that I probably won't go on TILT. Nevertheless, there's absolutely nothing wrong playing 1 table. Some regulars (that I know) only play one table at a time, and have been doing so for years, and make a monthly profit.
Remember, if you're playing NLHE, EVERYONE is playing it too! Most tournaments that you enter (specifically with S&G tournaments), are filled with players who are very knowledgeable. People tend to think that micro-stakes are filled with new players, but that's not really true. The less glamorous games like PLO, Omaha Hi/Lo, 2-7, stud games, Badugi, etc can be very exciting as well (with a softer field b/c the training sites focus primarily on HLHE and not the other games... though PLO has a solid following).
I hope that this info can help.
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