To write for the theatre you need to know about theatre. Ideas are easy to come by. Examine your background, interest, and beliefs. Examine the world around you. Exercises can help you come up with ideas. Choose the audience you want to reach and write to that audience. To learn to write dialogue listen to and record everyday conversations. Dialogue should sound like ordinary conversations but has more direction.
Know as much as you can about your central characters. Do a character analysis. Choose the character traits to emphasize. A character should come across as both typical and individual. Most plays have a plot, which involves conflict between the protagonist and the antagonist. The parts of a plot are: inciting incident, rising action, turning point, climax, and falling action. Other types of organization for a play are circular and thematic.
Before starting to write, you need to develop a central idea. Plays exist for a number of reasons—entertainment, to bring attention to something, and to teach. You need to decide what you want to accomplish. It’s easier to gain an audience’s interest if you start with a theme they agree with.
A play needs a sense of universality. A play should be unified, but it also needs contrast. Since theatre is a collaborative art, the director, actor, and designers may see the different facets differently than you do. It’s not difficult to have a well-written produced. Possible markets are schools, organizations, and professional theatre. Finished plays have to follow a particular format.