Avoid "acting" in your acting. ATC Founder, Carole Dibo, touches upon what an actor's use of their emotional library means in bringing life to a scene.
"Having the confidence to use your emotional library is a critical skill to avoid 'acting'. Peel back what the character is feeling in the scene or monologue (fear, loss, joy, etc.) & substitute the experience YOU had of that feeling. BAM! No 'acting' required."
-ATC Founder, Carole Dibo