Poker is a game of knowledge, skill, strategy and a little bit of luck. In poker, you can't control the cards you get (that's the luck), but you certainly can control when you put money in the pot. Poker isn't just about the hands you play, but the ones you don't and making good betting decisions means you keep more of your money and maybe take a little from your opponents at the same time.
There are a lot of variables that determine strategy - position, starting hand, pot odds, skill level - but for beginners, it can all be very overwhelming. So, if you learn at the onset to avoid common beginner mistakes, as you get better, you can study more, watch the pros play to analyze WHY they did what they did when they did, pay attention to the commentators' analysis and modify your game as your skill level improves.
STARTING HANDS - Most beginners play too many hands, especially in the stud and community variants, just to be part of the action. Understanding the odds of making a winning hand from your starter cards is crucial. If you don't think your hand is good enough to raise a bet, fold. Where you sit at the table - your position - makes a huge difference. You'll need stronger starting hands the more players in front of you waiting to act.
POSITION - Stud and community poker variants are nuanced and intricate, with so many variables that determine good play, but whether you should call, raise or fold is best determined by the cards you hold and your position at the table. For beginners, raise with big hands in early position (first or second to act) and play more hands in late position (seats nearest the dealer). If someone raises before you intimating a strong hand, play less marginal starting hands.
NARROW THE FIELD - When you have a good hand in a good position, it's your job to narrow the field as early as you can to keep players from making their hands later and beating yours. Your odds of winning go up with less competition.
COUNT YOUR OUTS - In stud and community-based games, like Texas Hold 'Em, where there are several rounds of betting in between dealt cards, it's important to know how many cards are out there that will improve your hand. Eliminate the cards you can see and the cards you hold. If you have determined you have 6 outs for the next card to improve your hand (6 cards will help you), multiply it by 2 and add 1. So, you have a 13% chance of getting a card you need on the next card dealt.
POT ODDS - Beginners call too much because they don't understand pot odds and they stay in hands long after they should have been out. Sure it involves a little math, but knowing the pot odds will determine whether you should pay to see more cards or get out early. Pot odds are the ratio of the size of the pot to the size of the bet (example: a $10 bet into a $50 pot is 5:1 - pay 1/5 of the pot to make 5 times the bet). Once you know your outs, you can better calculate the pot odds. So, in our example above, with 6 outs we have a 13% chance of getting a card that helps us. The current pot is $90 and the bet to us is $10. Pot+bet=$100. If you divide the bet by the pot amount ($10 divided by $100), you get 10%. In our case, we should call because we already determined we have a 13% chance of hitting a card we need to better our hand. If the bet was $20 (pot+bet=$110; $20 divided by $110), we would fold because we would need 18% or better pot odds to call.
4 AND 2 SHORTCUT - The 4 and 2 shortcut is helpful to beginners who aren't comfortable doing a ton of math in their heads. Calculate your outs, let's say 8. If you have 2 community cards coming (The Turn and The River in Texas Hold 'Em, for example), multiply 8 by 4. You have a 32% chance of hitting the card you need. If you still have 8 outs after its reveal, your chances go to 16% for the last card (8x2=16).
VALUE BET - A value bet is one made with the intention of increasing the value of the pot and it can be the difference between winning a bigger pot or not. The more an opponent believes their hand is good, the better the odds are they will call for more money. Even if the player thinks you can beat them, you can make a bet small enough that the pot odds are right to make a call, especially with those players who rely on mathematics. Players who are married to their hands - just not willing to fold a big hand no matter the pot odds - are likely to call value bets, even big ones. A scared player will have to be convinced to call. To be safe, you can assume a player's call amount threshold - how many chips they're likely to call in one bet - is half their stack. Knowing all this will help you decide on the size of your value bet. Bet too much and your opponent folds and you lose money. Bet too little and you win less. Your bet size has to be small enough to get called and large enough to cut the pot odds to anyone drawing to a better hand.
STANDARD RAISE - Beginners get excited when they get good cards and tend to overbet - raising big with Aces every time lets the table know you have something, probably Aces. The best way to camouflage the strength of your hand is to make the same bet size every time. Your opponents won't know what you're holding. Also, don't call unless you're ready for a raise and don't raise unless you're ready for a re-raise.
CONTINUATION BET - If you raised before the community cards are revealed and bet again after they are revealed, you've taken an aggressive stance telling the table that you liked your cards before and you still like your cards (whether you hit or not). Because most poker hands miss catching any cards on the board, a continuation bet takes advantage of the early initiative and your opponent is likely to fold. Many players put "dead money" into the pot early, which makes the continuation bet so powerful, however, in poker you cannot do anything 100% of the time. You will be found out, exploited and you will pay for it. And, as with all poker, there will always be a lot of variables to consider - the number of players left in the hand; board cards; opponents' style of play, etc.
BLUFFING - We've already established that in poker, the best hand doesn't always win because the player who actually has the best hand can get outplayed due to strategic betting. A player with nothing can make a bet or raise that pushes out the rest of the players and wins, without having to show his hand. Bluffing - strategic intimidation with a weak hand meant to convince other players that it is stronger than it is - is another poker strategy, but it's one that should be used wisely, and sparingly. Some players never bluff. Bluffing works best when you have one opponent, when you are in late position and no one before you has represented strength or when the board or cards you have showing intimate a good hand. Bluffing doesn't work with lots of opponents, players who never fold or with players with so much money in the pot any bet you make won't make them go away. Bluffing works in the right situations because poker is a game of incomplete information. Beginners have a tendency to bluff, rather than fold. However you bet with a good hand (big or small), bluff the same way or you'll be found out.
OBSERVE OTHER PLAYERS - As a beginner, you're already juggling a lot - remembering how to play, paying attention to your own hand and community cards, who bet what, your turn in the action. Once you've gotten that down, watch your opponents even when you've already folded. You can gather a lot of information from them - betting habits, number of cards exchanged (5 Card Draw, for example), showdown hands, how often they bluff (intimating strength when they have none). If you can zero in on your opponent's "tell," little gestures a player may not even know they have, you'll spot deception earlier and maybe capitalize on the information.
DISCONNECT FROM THE MONEY - To really play poker as intended, a player has to be disconnected from the money because they have to be ready at any time to move all of their chips into the pot. Money is the way poker players keep score and making money is a byproduct of winning. Don't play with money you can't afford to lose. As a beginner, you should be playing in home games, free online games or low-limit tables at the casino. The skill level of the players increases with the table limits, so in this case, being a big fish in a small pond works just fine.
Beginning players are sure to learn from big losses, but it's the small losses that add up, so the more knowledge you have and the discipline to have a reason for every move, you'll minimize the mistakes that cost you.