Poker takes a few minutes to learn, but a lifetime to master. But this is not to say that you can't make money as a total beginner, because when you start at the lowest stakes, you won't find many experts.
Each time we make a decision at the table - be it call, bet, raise, or fold - we weigh up the pros and cons of each action, in order to either maximise our gains, or minimise our losses. We want to take actions that have a positive expectation (profit), and avoid ones with a negative expectation (losses). Consciously or subconsciously, we use estimates of mathematical probabilities to make our decisions. We might make a decision to fold because “He probably has me beat”, or we might raise because “I think I have the best hand and he will probably call with worse”. Sometimes we're fairly sure we're behind, but we will call a bet because “There is a decent probability I will hit my flush, and win villain's stack”. Math can be a little scary, but you really don't need to be able to do complicated calculations at the table. Indeed, in this course, I'll be encouraging you to play a style that avoids tricky spots where your expectations are unclear.

Since poker is a game of incomplete information (we don't know our opponents' exact hole cards, or how they happen to feel about them) it is impossible to calculate the perfect bet-size to use each time you are faced with a decision. All we can do is see how our hole cards connect with the board, compare them with the likely holdings (the “range”) of an opponent and proceed accordingly. When we believe our relative hand-strength is stronger than villain's likely range of hand strengths, we will want to build a pot to maximise our expectation. If villain is likely to have a stronger range than us, and we don't have much chance to improve - or a cheap price to do so - we will usually get out of the pot to minimise our losses.

The fundamental idea for beating 2NL is as simple as this: We will bet and raise when we think we are ahead, and we will fold when we have reason to believe we are not.

Making money in poker in the long run isn't quite as simple as just value-betting our strong hands and folding our weaker ones, but that is the main strategy at 2NL. I'll write more on value-betting in my next article.

David Sklansky's Fundamental Theorem of Poker uses some complex verbiage that uses game theory to describe how we make a profit with poker, but it could perhaps be distilled down to the following sentence:
We make money at the poker table by making fewer – and smaller – mistakes than our opponents.
Everyone makes mistakes at 2NL. I'm not a automaton playing perfect poker and I don't expect my readers to be so. During a particularly good session, there might be hands where I could have squeaked out a bit more value, or situations where I should have found a fold on the turn rather than the river. I can beat the game comfortably, however, because most of my opponents make much bigger mistakes than I do and they make them more frequently.

At 2NL, your opponents will make many mistakes, ranging from small errors like limping pre-flop with a ragged ace, or calling 1c in the small blind with a suited connector, to BIG mistakes like calling river shoves on a wet board with just one pair.
The most obvious and common mistakes that 2NL players make are:

* Calling too often, both pre-flop and post-flop, with weak hands.
* Betting too small with their strong hands.
* Over-valuing their medium-strength hands.
* Chasing draws without the odds to do so.

If we want to make money, we will not make these mistakes.

An article detailing the most common leaks I see at 2NL is coming up soon. Hopefully you'll recognise a few of your mistakes and immediately stop making them.

But now it's time for our gameplan; a straightforward approach to beating the game.

* We will play only a couple of tables at once, so we can develop reads and take notes without being pressured to make quick decisions when we're involved in a hand.
* We will not play when we are tilted, tired, or feeling unwell, because our decision-making process will be compromised.
* We will play a tight range of starting hands that is stronger than that of an average 2NL villain.
* We will avoid playing out of position and without the initiative wherever possible, by playing very snug in early positions and the blinds, and by usually entering the pot with a raise, not a call.
* If we feel that we are being out-played by tough opponents, we will find a softer table, in order that we have a definite edge over at least one player.
* We will bet for value when we connect with the board.
* If we miss the flop, we shall make a continuation bet when appropriate. (An article on c-betting is coming up in a few weeks).
* We will rarely slowplay or get fancy with our monster hands, because we could miss value, face tricky decisions on later streets, or allow the villain to draw out cheaply.
* Other than c-betting, we will rarely bluff.
* If we face a tough decision, we will be more inclined to fold than call/raise, and after the session we will post the hand history in the PSO forum for advice.
* We will accept that luck plays a role in poker. We cannot control our luck, so we will focus on making correct decisions.
* We will take bad beats and suckouts with good grace, knowing that we will make money in the long run by making better decisions than our opponents.

Some of the points above are also mentioned in Roland GTX's excellent forum post HERE.

In the next article, I'll have more on value-betting, with a graph showing that having the best hand at showdown is crucial to beating 2NL.

Questions and comments are welcomed, as usual.

Cheers!