Use Of Set, Props and Costume In Brecht

Brecht believed the stage should be brightly lit at all times; special effects to create mood were not allowed. (Logically, he could have allowed it, if accompanied by some device to draw attention to it - such as a statement from a character.) The sources of light should be plainly visible - just as those over a boxing-ring (Brecht's comparison).

The curtain is to be used for the display of titles, captions or comments. Placards may be placed in the auditorium, bearing instructions, such as “Don't stare so romantically” (from Drums in the Night). The set behind the curtain is suggestive, not realistic; that is to say, while very authentic props may be used, (as, say, Mother Courage's handcart) there will be no elaborate arrangement of these in a naturalistic stage set.

The music, too, must have a visible source - musicians may even be on the stage. Interruptions for songs are announced or indicated by projection of a title, or flags and trumpets will descend from the flies.

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Brecht developed a style of theatre known as epic theatre. He believed that in conventional theatre the audience hung up their minds with their coats as they entered the theatre. He wanted to remind the audience that they were watching a play. He used representations of characters instead of real characters. He encouraged the actors to talk to the audience before the play began. He used minimal props; usually only one per character. There was a use of character labels. a half curtain across the stage was also a feature, and the actors changed costumes on stage. The characters changed costumes on set because they wanted enforce the idea that the actor's were not completely one with the character. In making this distinction, they helped break the fourth wall between the audience and the stage. Brecht did not want the audience to be comfortable with the pla, instead he wanted them to judge society and go out to make a difference. Not one of Brecht's stage directions is a mistake, he strongly believed in the 'Alienation Effect' which means to make something strange and stand out so that the audience sees something in a fresh and new way. In doing so, the audience can see the didactism (another one of his theories) which is basically showing that each play has a political or social moral found in it. 
Brecht also invented Gestus which has everything to do with movements, sounds, etc that the character will perform. In these movements the actor will portray to the audience the emotion trying to be perceived. He wanted the audience to see a specific motion and make them then relate it to a social or political flaw. He encouraged keeping "Model Books" in which the director had photos and intense notes on the piece at hand. That way, when going back, the director could remember each distinct 'gesuts'.
 

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