Can't be a tragedy with a small voice, please don't mumble. Can't just be in your head, physicalize it. Cinematographer makes pictures. Comes down to the human face, not just special effects. Connect with other actor, the stimulus.
Conversation is behavior, do things that say things, it is body language .
Add behavior, tells you more than dialogue. It is to decide emotion and objective which is the cause of action and words. Don't get into tricks, it's superficial, so mannered and phony. Dialogue doesn't fit behavior. Do not fall in love with one thing, try many different ways as an actor.