Of all the questions young people ask about acting these two make me most frustrated: 1). Is such and such a big role? and 2) How shall I play my role? The reason these questions bother me so much is that they illustrate that the asker is not really into the theatre and acting. Those who ask how big their parts are obviously have no patience. When they go to rehearsal, they will find out. Or they have never heard of Stanislavsky's famous saying "There are no small parts, only small actors." This means that there are no insignifican parts, only insignificant actors. Every part in a play is put there by the playwright to help make the play better. As far as the effectiveness of the play is concerned all parts are equal in importance. When I was directing, i fequently said that the chorus parts in musicals were more important than the leads as far as casting was concerned. Everyone wanted to play the leads. It sometimes was difficult to find chorus members. When I was acting in films, I did not always have the support of my administrators. Once in a meeting with my department chairman and the dean of our school, one of them denigrated my film acting saying, "That is only a small part." I replied that in the theatre we believed that there were no small parts. One of them said, "You don't really believe that?" I said, "Of course I do." And I still do. Every role in every play is as important as every other role.
Now asking about how to play one's role is a question that occurs to many actors. The problem is whom you ask. If you ask anyone but the director of the show about how to play your role, you are being disloyal to the director. As a director, it is their job to make sure each actor plays their role well. When you ask anyone else,you are undercutting the director's job and authority. It is also an unprofessional way to behave. In many theatres it is cause for being dismissed from the show to ask anyone except the director for help in playing your part. Avoid it at all costs. Conversly, it is just as bad an offense to offer help to someone whether they ask for help or not.
Respect the director and the playwright. Make sure you seek information for the right reason and from the right person.