In acting class, play the script not the movie or the actor. When we first start acting we start emulating the people we see on television and in movies. This is a first level for many actors as they are beginning. Yet, it is important to move past this point ASAP. This is because, as a professional, you will never be asked to play somebody else or to redo that film. What you will be asked to do, is to feel real emotion and portray real communication.
In acting class, we learn script analysis. Everything is right there in the script. When you are redoing a scene, often times you need to edit the stage directions so that they are applicable to your particular location. Feel free to change these ancillary details. But I would warn you to stay with the dialogue in the script, in general. It’s good training to be able to adapt to the script. Adaptation is the actor’s most important ability. You will adapt to the script, to the director, to the set, and to the crew. This means that all your fears and ego must be put aside in favor of establishing a positive and creative vibe with all of these people. They should also be adapting to you.
It is a strange and counterintuitive reality of acting: As you become another, you are able to better become yourself.