In addition to her work on the stage, Manley performed as a reader on Los Angeles' highly respected public radio station, KPFK, where she interpreted (among others) the work of Anais Nin, Lawrence Durrell, Herman Melville, Edgar Allen Poe, Meridel LeSeuer, and Oscar Wilde.

Manley also distinguished herself as a teacher of acting and voice. She was a founding member of the Theater School at the California Institute of the Arts, and she taught privately for many years as well. Among her students are Paul Reubens, Bill Irwin, and Ed Harris. In 1990, she was awarded an honorary doctorate by Cal Arts for her work as a teacher.

Manley wrote three books on acting, five plays, two librettos and a screenplay. Two of her books, My Breath in Art: Acting From Within and An Actor's Dickens: 80 Scenes for Audition and Performance from the Works of Charles Dickens are published by Applause Books, the premier publisher of books on theater and cinema in the United States.