Well, first of all, there's usually a trigger for the hypnosis. It could be a swinging object, like a pendulum, or a repeated pattern of words. Then, for a girl hypnotized story, the girl's reaction during hypnosis is a big part. She might be calm, or she might start to see things in her mind as if they were real. And finally, there's often an end to the hypnosis, where she either wakes up suddenly or gradually, and may or may not remember what happened during the hypnotized state. For example, in a story where a girl is hypnotized at a fair, the magician might use a shiny object as a trigger, the girl could start dancing as a reaction, and then wake up at the end of the show not fully remembering the dance she did while hypnotized.
Common elements include the initial state of the girl before hypnosis, like being curious or having some sort of problem that hypnosis is supposed to solve. There is also the process of being hypnotized, which might involve relaxation techniques. For instance, in a story about a girl trying to quit smoking through hypnosis, she would first be in a state of wanting to change. Then, during hypnosis, the hypnotist would likely guide her into a deep relaxation. And finally, the outcome of the hypnosis, whether it's successful or not. In this case, if the girl no longer has the urge to smoke after the hypnosis, that's a successful outcome. In many girl hypnotized stories, these elements are used to create an interesting and engaging narrative.