A: Well not being a psychologist, that would be tough for me to answer. So the only thing I can share is my own interpretation of what you want to know from this question.
Interpreting a response means that I go inside my own head and hallucinate the meaning. In most cases that won't do me or the client any good. Instead I can notice the response, and see if it fits the response I was aiming to elicit. If not, then I can change my approach, until I get the response I am after or decide to go for something else altogether.
And the best way to notice responses is to go into an uptime trance. Meaning get out of your own head and pay attention to the person sitting in front of you. Remember: that's why they are paying you!
Once you pay attention to the client, you will become aware of their current trance. And in most cases, it is not serving them, and that is why they are there to see you. Now as a skilled hypnotist, you can find out where they currently are and where they would like to be. And using a variety of hypnotic tools, you can easily guide them there.
And during the journey, you will notice all sorts of responses. And these responses let you know if you are on the right track or not. This is where sensory acuity and knowing what the client wants, comes into play.
So there is no need to interpret anything, especially when the client is right in front of you. If you aren't sure, just ask. They'll steer you in the right direction if you are off.
It is very simple, so keep it simple. And anyone can do well with hypnosis!
-Oz