Preemptive Adjustments Based on Population Tendencies

Image Credit - Yanning Van De Wouwer

This concept can sound complicated, but it's actually fairly straightforward in practice. The sooner you start deviating from your standard poker strategy the better and by being aware of population tendencies you can make some small initial adjustments before you even have the chance to know your particular opponent.That's why you should adjust your default strategy right of the bat and thin value bet more often, add some combinations of mindless spazzes to villains range (but at the same time you shouldn't be hero calling often due to average villain's passivity) and use very wide exploitable stealing ranges expecting to auto-profit preflop.

Conversely your average opponent in Zoom NL500 games will be a competent regular with a good amount of knowledge about poker. That's why you can't get away with raising 70% of your buttons and expecting to auto profit with your wide 3betting range vs. button open.

Adjusting vs. Bad-Passive Opponent

Image Credit - Danny Maxwell

How to Spot a Bad-Passive Opponent

• Huge gap between the VPIP and PFR (40/9, 63/15, 55/6 etc.)
• Limping preflop.
• Very small 3bets.
• Small fold to cbet.
• Low aggression factor.
• High went to showdown.

How to Adjust Your Poker Style

• Isolate his limps often with a wide variety of hands, particularly the ones that often make strong top and second pair hands (for example KJo, J9s, QTo, A9o etc.).
• Value bet thin. Since villain's range is very wide and he tends to call too much you shouldn't shy away from going for three streets of value with your top pair type hands on favorable boards. While playing second pair type hands passively, in order to strengthen your checking range makes a lot of sense vs. other player types, you should consider value betting them vs. bad-passive player.
• Don't bother cbetting with the bottom of your range. You shouldn't completely forgo bluffing, some passive players fold often enough for you to make frequent exploitable cbets with weak hands, but this often won't be the case and you should focus on thin value betting instead of stealing pots.
• Avoid big bluffs. Again, this is not an axiom. Some bad-passive players fold often to the turn and river barrels, but most of them won't. 
• Use exploitable betsizing. Many passive players have static calling ranges. This means that their ranges won't change whether you make a 1/2 pot size value bet or you're smashing the pot button. While no range is truly static (even the worst opponent might fold if you overbet the pot significantly) you can easily increase your expected value by simply betting more when you have it and less when you don't. Which leads us to another point.
• Balancing doesn't matter. Bad passive players simply don't pay enough attention and you should use that to your advantage.
• Lastly, if a passive opponent makes an aggressive action you should believe him and get out of the way unless you're near enough the top of your range to justify defending.

Adjusting vs. Bad-Aggressive Opponent

How to Spot a Bad-Agressive Opponent

• High VPIP and PFR (38/25, 44/39, 31/30 etc.).
• High 3bet frequency.
• High 2nd and 3rd barrel frequency.
• High aggression factor.
• High raise cbet, check/raise etc.
• High W$WSF.

How to Adjust Your Poker Play Style

• Defend vs. open raises and 3bet with slightly wider but still strong ranges, including hands that can flop good top and second pair bluff catchers.
• Value bet thin. This point might be surprising, but it's still correct to go for frequent value bets vs. bad-aggressive opponent as long as you adjust for the fact that your bets can sometimes induce a bluff.
• Cbet often. Players with high aggression factor will give you more trouble by raising your cbets, but at the same time you can't have high AF when you're calling a lot. Many bad-aggressive players fold way to often to your own bluffs.
• Get ready for big calls. This will vary depending on your opponent's level of aggression, but vs. some villains it might be correct to go for hero calldowns that you wouldn't normally consider. Don't get carried away though. Always think about the ranges and adjust accordingly.
• Consider slowplaying the top of your range. While bad-aggressive players will often pay you off if you decide to go for conventional value betting lines, it's often a good idea to give villain a chance to spazz out with the bottom part of his range that you wouldn't get any calls from.
• Keep your mindset in check. Playing against bad-aggressive players can be very frustrating. The constant pressure can put you on tilt and cause you to lose chips you wouldn't have lost in normal circumstances. Be aware of your feelings and use breaks in critical moments.

Adjusting vs. Good-Aggressive Opponent

How to Spot a Good-Aggressive Opponent

• Low gap between VPIP and PFR (18/15, 22/18, 28/23 etc.)
• High 3bet frequency.
• High cbet.
• Moderate fold to cbet.
• Low cold call preflop.
• Low to moderate WTSD.

How to Adjust Your Poker Style

• Make sure you defend with adequate % of hands. If a good passive opponent is stealing often from the button you should take advantage of good odds and defend many hands in the big blind. If he's 3betting a lot, you should start defending.
• Conversely, take advantage from villain's unbalanced ranges. Many good regs, especially at lower limits have a bunch of small leaks that often include folding too often vs. steal and 3bet. Open up your ranges in those spots in order to exploit those common leaks.
• Make notes. Good-aggressive players don't have as many obvious leaks as bad players, but there's no such thing as the perfect poker player. Everyone has holes in his or her game and you should make sure you're aware of your opponent's shortcomings by making adequate notes every time you see them. For more on note taking, check out this article on TPE.
• Database analysis. Another great way of figuring our other regulars leaks is putting some work away from the table and analyzing their game in your tracking software. While this might not be worthwhile if the player pool at your limit is very large, if you find yourself playing against the same opponents over and over again you should consider using filters in your database to learn their leaks and use that knowledge at the table.

What about good-passive opponents?