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I didn't learn posing from a book so I can't recommend any. I recommend standing in front of a full length mirror yourself to learn.
Imagine you are walking on a narrow sidewalk and you meet two other people head on. If someone doesn't turn sideways when passing you'd knock each other off the path. It's a test of dominance vs. submission to see who will turn sideways. As they approach you read their body language clues to decide for yourself whether to "stand your ground" or turn to let them pass. I do both at various times just to see how the other people will react. I'll just stop as they approach, but not turn sideways to let them pass, sending the message with my body language that just because there or two of them and one of me doesn't mean they own the public sidewalk. If forces one or both to turn or step off the sidewalk to get by.
Karen lives where body language was refined as a very effective defensive weapon. The Maori people used scary tattooed faces and crazy aggressive looking body language postures to intimidate potential foes. One look at them and the opponent would think, "Hell no, I ain't messing with that crazy dude".
You'd react the same way if walking down a dark street at night and you saw three guys hanging around on the corner. If you are were risk adverse you'd cross to the other side of the street and if they made a move to cross also start running as fast as you could. If you don't pick up on signals like that you become easy prey because the criminal element are experts at reading the body language of "marks". If you make some overt effort to show them you are aware of them, like crossing the street, they'll usually leave you alone because they see you aren't an easy target.
Knowing how to pose a subject in a photo is just learning to consciously recognize body language signals like that and use them to manipulate viewer's reaction in the same ways. To do it effectively you need to understand what postures trigger a passive/aggressive, confident/shy, sexy/demure reaction in real life and in photos.
Start first by thinking about how you react to the clues in photos. If a woman in a photo you see looks shy or demure notice how the shoulder's eyes and hips are angled. You'll see shallow angles that appear to fall off front>back. What happens when the model thrusts her hips a bit more and cocks the shoulders down at a steeper angle into the camera is that her body language changes from passive to aggressive. The greater the tilt the more aggressive the posture looks.
In terms of actual posing mechanics all you need to do to get the model to go from "demure" to "sexy" is have her increase and exaggerate the shift her weight more to one hip. The hip bone is connected to the spine, which is connected to the shoulders, and shoulder line will follow the hip to create the more aggressive "sexy" body language.
Ask a non-model to pose for a photo and what to 90% of the people do? Stand flat footed and square to the camera and grasp their hand together in front in a "fig leaf" pose. So for comparison use squared off and flat footed as the starting baseline: hips, shoulders, and eyes will be level.
What impression does that give you? Passive/ Aggressive? Dominant / Submissive? Compare with arms grasped in front to arms hanging naturally at sides and crossed in front. How do the arms change the body language?
Next angle the entire body 45 degrees to the camera. You do that by asking the model to put one foot in front of the other. Start with them flat footed, weight equal on both feet: Compared to the first baseline does the more slender overall profile seem more passive/submissive?
Next have them shift weight to back hip to the point they can lift the front heel off the ground. Note how it shifts the hip and shoulder together. How does the angle affect their body language? Have them shift more or less weight to the hip to change the angles. How does it affect the body language.
Next reverse the weight shift to to the front hip. How does that change the hip/shoulder angle and body language message.
What you'll notice is that however you get the subject to shift the weight between feet their eye line will always wind up square and level. That's because regardless of body angle we adjust the head naturally to orient the eyes with the horizon. But in a photo you nearly always want the eyes at an angle and must continually coach a non-model who will constantly move their eyes back to level.
Something trained models also learn to do is shift hips, shoulders, and eye lines INDEPENDENTLY. By that I mean differently than they naturally wind up when with the weight shift of the hips. They do that to change the body language signals to something that subliminally trigger a "that doesn't look normal" reaction to the body language. Tell a trained model to look "sexy" or "demure" and she'll know from training and experience how to change the body angle clues to create that impression.
I reiterate, strongly, my suggestion to practice yourself in front of a mirror with square vs. oblique and different weight shifts between feet so you can understand where the hips, shoulders, eyes wind up naturally and how it feels. Once you understand the natural postural relationship of the feet weighting to hips and shoulders, you'll gain the insight to look at a shot of a model in a magazine and consciously be aware of whether its a "natural" posture creating the look or she's moving the hips/shoulders/eyes it a way they don't naturally fall into place with that foot position / hip angle.
In other words, once you understand the "feet up" dynamic of a natural pose you'll be able to "reverse-engineer" any pose you see starting with the "Wow that looks sexy!" emotional reaction, then looking at the angles of eyes, shoulders and hips relative to the frame, then comparing them to the "natural" postures you see in the mirror when standing flat footed or with weight shifted more to the front or back foot.
When you get to that point, which doesn't take long if you actually try what I suggest, when posing a subject your first thought will not be which "playbook" stick figure diagram to use but whether you want the wife to look demure or sexy, confident and shy. You'll be able to get any of them by telling her where to put her feet and shift her weight.
It's really that easy. I know because was very easy to grasp it when my mentor Monte Zucker demonstrated it. He had learned it from his mentor Joe Zeltman who noticed how foot position and weighting predicted the angles of hips and shoulders.