1. Playing Too Many Hands
An early lesson in poker is to realize the majority of hands you are dealt must be folded. I've known an amateur player turn round to me and say You've got to play the hand you are dealt, why fold. I was shocked and soon put them right. However, there are a lot of beginners that seem to ignore this most basic rule.
They will call with ace-rag out of position, even call a raise with it, they play any two suited cards or even any picture card. You can get away with playing loose like this in a game of no limit hold em but you must have a strong post-flop ability to be able to pull it off.
Situation dependent, most of the time you are looking to only play premium hands such as high pocket pairs, and very strong aces. Simply fold the rest.
2. Not Folding Mediocre Hands
After the flop has hit, amateur players find it very difficult to let go of marginal hands. Suppose they hit middle pair or top pair with top kicker, the will find it hard to lay down. Its a crazy situation to still be involved in a pot holding top pair when there are flush and straight draws on the board and players are betting like theres no tomorrow. I've seen people play online when they will see their hole cards all the way to the river even though the board has paired up, AND there is 4-to-a-flush on the board, AND a straight possibility. They just wouldn't let go of their flopped top pair.
The best hand on the flop may not always be the best hand on the river. Play with caution and don't be afraid to get out if the action heats up and you are holding a marginal hand.
A good way to look at it is to look at the board and think to yourself "What two cards could my opponent be holding for them to beat me?". If you can narrow it down to one or at most two sets of hole cards you should be fairly confident in carrying on playing. If you have to say to yourself "I hope he doesn't have X, or Y, or Z, or A, or B or C..." then you should really think about folding. The more combinations of cards that your opponent could be holding that beat your hand, then the more likely it is they are holding one of them. If there is only one or possibly two combinations of cards that beat you then continue to play but with caution. Bet out or raise to gain information on how good your hand is. If they fold, you win the pot, if you are raised then you are probably beat.
There's no shame in folding. Remember, especially in a tournament, poker scores are based on the player that loses the least amount of chips.
3. Under-Betting The Pot
In no limit texas hold em you can bet out as much of your stack as you like in order to protect your hand. You should be using this to your advantage. Weaker inexperienced players on the other hand tend to bet small amounts such as $30 into a $500 pot. These kinds of bets offer good players fantastic pot odds to call and suck-out on the river because of the money they stand to make in relation to how much it costs to see another card. A bet of around 75% of the pot is enough to discourage players on a draw. Any bet under half the pot is normally not enough.
4. Over betting The Pot
It is an easy mistake that amateurs make. They make a half-decent hand and the adrenaline kicks in and they decide to over bet the pot by pumping $300 into a $90 pot, or they move all in pre-flop for 1500 in a sit-n-go while blinds are still 15/30. The trouble with doing this, is that it makes hands weaker than yours fold, while hands stronger than yours call. By consistently over betting the pot you are either going to win a small pot, or lose a big one. Quite clearly not the optimum poker playing approach.
5. Ignoring Position
Knowledge is power in the game of no limit hold em. The more information you hold about the round of betting the better position you are in to act on this information. Playing hands under the gun means if you bet out, you could face a massive re-raise from a later position. You could check post flop in the hope of a check raise but instead find the entire table checks after you. If you are playing from a later position you have the ability to see what the rest of the table is doing before you act.
Amateur players will often ignore position and play a certain set of hands regardless of position. you should be playing only premium hands in early position, and then widening your range of starting hands the later your position becomes. TJ's plays badly from UTG but very well from a late position.
6. Failing To Protect Your Hand
Many amateur players are guilty of playing far too passively. They will simply check or call unless they are 100% sure they have the best hand in which case they will raise. By failing to bet, or failing to raise they will make it easier for their opponents to draw out on them who might otherwise have folded. If you find yourself against a tight passive player, raise more often than you usually would and you can find yourself winning a lot of small pots.
7. chasing unprofitable draws
Playing a drawing hand is only ever going to be as good as the value of the pot you are trying to win. You should always fold if someone makes a bet where you are no longer getting correct pot odds to call. Amatuer players make the mistake of ignoring these odds and will call all the way to the river in the hope that they hit. It is possible they do not even understand pot odds or know what they are.
As frustrating as it is when monkey players like these suck out on the river you have to remember that they are playing bad unprofitable poker and they will end up losing more money than they win. Just make sure you are in the pot when they lose
8. Bad Stack Management
Amatuer players often neglect their stack size when it comes to playing holdem. If you are playing a cash game you should always have around 20 big blinds to capitalise on your monster hands. If you are falling short, then reload your stack. There's no point hanging on with £50 in a £5/£10 cash game only to flop quads next hand and miss out on a huge pot. If you are playing a freezeout tournament, you should stop calling pre-flop when you are between 10 times the big blind (worrying) to 5 times the big blind (critical). There is no option but to push all in with any Ace, pocket pair, suited connectors or any hand under the gun.
You are looking to have enough chips to maximise your big hands, or to keep you alive in tourmanet situations. Bad players will flat call hands when their stack is 5 to 10 x BB. Good players will push all in. Bad players will not reload their chips in a cash game, good players will.
9. Adapting Your Style
There is a big difference between playing cash games and playing tournaments. In cash games you have to be prepared to put your entire stack over the line when you know you are going to win more times than you lose, when you have a positive expected value (+EV). If you lose then you can just reload. In a tournament you have to be more protective of your stack as if it goes then your are out of the game. There are many other subtle levels, but these are the fundamental differences between the two games. Bad players are those that do not adapt their game accordingly and play tournament strategy in a cash game and cash strategy in a tournament game.
10. Trying To Imitate The Pros
The generation of poker players coming through nowadays are those raised on watching it on TV. People have their favourite poker players they have seen making big bluffs and talking the talk. Amatuer players seem to copy-cat these actions in order to come across more professional. what they fail to realise however that on TV they are only watching edited highlights. Not every hand is a monster raise, or a trap, or a bluff - in fact most of the time it is one player raising with a genuine hand and everyone else folding. This is unfortunately the less interesting side of poker but it (should) represent a large majority of your game.
We have a generic nickname for these kinds of players at the table. Those that come in wearing the shades, the cap, the iPod, talking about how other players should have played their hands, talking crap. The nickname given is "All the gear, no idea". Make sure you are able to spot these players if they are on your table and more importantly make sure that you are not one of them yourself!