The basic principle of posing for a stills camera is...

Keep still and be natural.

Let me rephrase that...

Stay where you are asked to
and feel relaxed and comfortable inside.

 
There are 2 types of posing.
One is the "America's top Model" type, where the model tosses their head and moves every shot to get "Bazang" photos.
I hate that.
 
Simply let the photographer set you up in position,
the best position,
and stay there.
 
Why change when you are in the best position?
 
The most important thing is not to worry.
 
If I am doing your photos, you have complete control over the outcome.
 
Over 30 years, I have figured out how to pose for each individual.
It is very subjective and personal.
I will assess you, and work within your preferences, then come up with some ideas, and I will teach you how to pose.
Every person is different.