It is also essential to give your actors something, in every moment, to do.
David Mamet (p.13, 1998) cites an un-sourced quotation by Bertolt Brecht:
‘Nothing in life is as interesting as a man trying to get a knot out of his shoelace.’
The person with attention directed outward becomes various and provocative.”
No-one 'does' nothing, in every moment we are doing, we are in a state of ‘being’ -
You have to identify what the nature of that 'being' is,
in order to bring your character to life...give your character/actor a life to ‘live’.