Simple , honest , vocal. Cannot take every big moment and turn it into radio. Vocalize, make it loudly. The problem is to deal with big moments. They don't have to be loud.
First beginners try to do tricks with face.
Instead, substitute for feelings . You can't act with face. Stir the imagination of audience with feeling and thought. Stop acting, get involved emotionally, can't act with brain, must be feeling . To act you must be overcome with feeling .