Pre Flop

Playing reasonably well preflop is very important, and most people don't do it.  The first big step is to play tight.  You make most of your money from the Sklansky Group I hands (AA,KK,QQ,JJ,AKs).  You need to focus on playing those hands.  You'll play a lot of other hands as well in various situations, but the funny thing is that if you folded every other hand, it wouldn't be that bad.  Next, you start considering various other hands.

I'm not going to go through a lot of hand groups and specific scenarios.  I don't enjoy memorizing a lot of rules, and I bet you don't either.  By this point you should have some idea of the factors that drive poker - what hands are your opponent likely to have, are you drawing or leading, how much are you likely to win, what's the long-term EV of each move, etc.  So, in each situation, you can make a decision  based on the exact play, the players, and the cards you have.  Another eason not to go into too many specific rules is that they aren't really that valuable.  The problem is that there are so many situations you can be in, and the exact players involved makes a big difference.  Let's say you're in late position and some people have come in ahead of you.  Which position exactly opened it?  Was it a raise or limp?  Is he tight or loose, what about the people who called?  

Instead, we'll go over the principles that determine preflop play, and then we'll go over some example scenarios where you can see them applied.  You should then be able to apply those principles to all the situations you will face.  At each point you're using considerations like the ones we described in "Bayesian Poker".  You're putting your opponents on a range of hands.  Anyone who has not yet acted preflop has a random hand.  Anyone who has acted has a hand based on what they would have done in that situation.  You can then see how your hand compares to their possible hands, and imagine what might come on the flop and how the EV will play out.

There're no actual poker hands pre-flop, so being "ahead" just means you are more likely to wind up with the best hand.  When you have a pocket pair you are gaurenteed to make at least a pair, so we say you have a "made hand" as opposed to a drawing hand.  When you think of how to play a hand, you need to consider the EV tree and the sum over probabilities going into the future.  You need to consider what kind of flops can come, how likely it is for it to be a flop that you like, and then roughly how it will go after that.  You do this for your two options - calling or raising, and you see which way is better.

In more detail, for each case that you are considering, you sum over the EV of the various things that can happen, weighted by the probability of that event.  The things you have to think about are - various numbers of people coming in behind you, whether they raise or just call, what comes on the flop, then what your chance of winning is after that.

Note that you're thinking about what kind of flops can come and how you will play them.  You're also thinking about your opponents and what kind of mistakes they make and how you can take advantage of those mistakes.  This is even more pronounced in No Limit Hold'Em.  In No Limit, you are trying to win your opponents' stack - not the pot.  So, you should play hole cards that you think will let you win their stack.  Exactly what these are depends on the kinds of mistakes your opponent can make, but usually it's drawing hands, or hands that can surprise them.

The basic principles that we consider are :

1. Likely opposing hands, dominance, chance of winning

2. Draws, implied odds - how much you're likely to win, what kind of flops you really want to see

3. Reducing the field

4. How others see your play (slow-play or taking the lead)

Now we'll go over these in more detail.  To begin, we need to first establish the basic ideas of how you and your opponents will play pre-flop.  We need to start with this because you're going to use it to determine how you play.

You're going to play a lot more hands from late position; you should come in with only very good hands from early position.  You'll come in for a raise with more hands than you'll call a raise with.  If only a few people are in, you're playing "made hands" (like AQ), while if a lot of people are in, you can play "drawing hands" (like A2s).  If someone raises after others are already in, they probably have a very good hand.

The first thing you consider is how likely you are to be ahead and what you're likely to be up against.  This depends a lot on how many people are already in, how they play, and what they did.  For example, if a tight player has come in from early position for a raise, you're almost certainly up against a very good hand.  That doesn't yet mean you should fold, we'll get to that later.  Anyone who isn't in the hand yet has a random hand.  If there are a lot of people behind you with unknown hands, it becomes very likely that one of them has a very good hand.  For example, the chance of any one player have a Group 1 hand is roughly 5% [@@], but if you are in first position, there's a 25% [@@] chance that someone behind you has a Group 1 hand.  For the people behind you with random hands, you won't usually actually be facing those random hands, rather they will fold the bad hands and play the good ones.  So, you're really looking at the chance of them having a good hand, and then what kind of hands they will play.  Generally after you come into the hand, their standards will get even higher, but they will also play drawing hands.

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