Many people speak of alienating the audience (making them separate from the action) but verfremdungseffekt actually translates more closely to ‘distancing.’ However, it’s still often called the alienation effect or is shortened to the ‘v’ effect and there are many ways of using it.
Brecht definitely wanted his audience to remain interested and engaged by the drama otherwise his message would be lost. It was emotional investment in the characters he aimed to avoid.
His approach to theatre suits work which has a political, social or moral message. Perhaps you want the audience to consider the meaning in a parable (a story with a wider moral message). You might want to explore a theme or issue and make your audience consider varying viewpoints or sides to an argument. If so you can learn a lot from the distancing devices used in Brechtian theatre.
Epic theatre (Brechtian theatre) breaks the fourth wall, the imaginary wall between the actors and audience which keeps them as observers. They are active members of the theatrical experience as they are kept thinking throughout, not switching off.