Art Has No Rules
You can't teach a model how to pose because art has no rules. Unlike the photographer's job, which is sometimes very technical, a model's job is all about being. This isn't to say a model can't learn to pose, and herein lies the paradox. Throughout the course of a model's career, she will constantly be bombarded with tips and tricks on how she should pose. Photographers will tell her "never do this" or "always do that".
I say screw em (not literally). It's like that popular saying "rules are made to be broken". If you're at the studio, in front of the camera, and a myriad of posing rules are going through your head, you are practicing a detrimental form of self-censorship. Your movements are predetermined and lack the spontaneity required to produce art.
Learning how to pose isn't done by taking notes and adhering to all the rules. It's done with practice, intention, and authentic confidence. No matter how much the evil forces in this world try to eliminate individualism, as humans, we are all different. So why do we pretend that the same posing tips and tricks will work for everyone?
It's incredibly difficult to even give advice to new models, because everyone's modeling journey is different. Some people will pretend that there are coveted secrets to modeling, and if you are privy to them, you will no doubt be an amazing model. This could not be further from reality.
There are no secrets, just truth, and the truth is that good modeling does not result from striking poses. Good modeling comes from being, from feeling, from expressing. The only advice I can offer an aspiring model is to dive in with enthusiasm, create with intent, be authentic, find your style, and don't let people tell you what to do too often.