Poker

I used to play poker all the time in high school. I’d watch Celebrity Poker Showdown and play with friends on the weekend. Lately, I play poker once a year during Sentry’s Hack Week. This cheatsheet is all the basic information I use while I play.

Skills

• Reading the other players. Watching their behaviour, taking notes, assigning roles and personalities
• Calculating outs, probabilities, pot odds based on the position and stack size
• Reviewing the hands later to correct the lines
• Varying the play style to stay unpredictable

Attitudes

The most important attitude is to be process oriented, not results oriented. In poker, even good decision-making can be punished by randomness. It’s important to evaluate the outcomes based on whether they were caused by sound decisions or not (applies to both winning and losing).

The main aspects of poker (like hand selection) depend hugely on position and stack size, just as much as the actual hand.

Stack Size

• ~100 BB is healthy
• < 5 BB go all in

Range

Range evaluation is important in poker. The range is the set of hands that are viable for a given player. Ranges are used to estimate and evaluate what hand a player might reasonably have at any given time. e.g., a low-stack on the button has a wide range, they could be playing anything. Another player might have a narrow range, especially if they’re playing on the bubble in a tournament setting. Ranges widen somewhat with a larger stack, and a lot with fewer players.

M

M is the number of full button rotations you can survive just paying the blinds.

• ~30 is healthy
• >20 means play as usual
• <15 start being aggressive
• <5 play the next decent hand

NOTE: M affects other people’s range. High-M players and low-M players have wider ranges due to comfort and desperation respectively.

Hand Evaluation

Bet Sizing

• Pre-flop betting ~3× the big blind is standard
• Raise in multiples of the previous raise, usually
• Bet in fractions of the pot

Pre-Flop Play

• Get people with trash cards to fold
• Get money into the pot
• Protect strong hands from flukes

Post-Flop Play

• C-bet almost always if you were the pre-flop aggressor
• Check to the raiser almost always if you were not the aggressor
• Raising into the aggressor is a “donk” bet
• Bet aggressively on wet flops to push out draws

Counting Outs

An out is a card left in the deck that gives you the hand you need.

Rule of 4 and 2

Roughly 50 cards are unknown, so:

• On the flop: outs × 4 ≈ % chance of winning (6 outs → ~24%)
• On the turn: outs × 2 ≈ % chance of winning

Odds Against

Odds against is the ratio of unhelpful cards : helpful cards left. e.g., the board is Kc 7d 4s Jc, and the hand is Ac 3c, drawing to a flush. 9 clubs left, 46 unknown cards → 9 helpful, 37 unhelpful makes the odds against 4.1:1.

Pot Odds

Pot odds is the ratio of money already in the pot : amount required to call. e.g., if an opponent bets $20 into a $50 pot, it’s $20 to call a $70 pot which is 3.5:1 pot odds.

Calculating Odds

Pot odds > odds against → call Odds against > pot odds → fold

NOTE: this is where “protecting the hand” happens. If you give your opponent bad pot odds they will more likely fold.

Reading Players

Table Image

• Tight vs. loose
• Passive vs. aggressive
• Betting history
• Tilt
• Level

Levelling

• Level 0 is thinking about your cards alone
• Level 1 is thinking about your cards + what your opponent might have
• Level 2 is thinking about your cards + their cards + what they think you have

Varying the Strategy

Play consistently well without being readable by assigning percentages to actions. e.g., with A 10 on the button, raise 60% of the time, check 40% of the time.