In "The Story of an Hour" what clues does Kate Chopin provide to the theme of the piece?
It depends on what you think the theme of the piece is. If you think it is about the roles of women in marriage, and how this particular woman was not happy in those roles, there are several clues. The first is when Chopin describes Louise's appearance: "She was young, with a fair, calm face, whose lines bespoke repression and even a certain strength." Chopin mentions that her face reflected "repression"; so, the woman felt repressed in her role as a wife. Then, as Louise looks out the window after hearing of the tragedy of her husband's death, she sees "the tops of trees that were all aquiver with the new spring life. The delicious breath of rain was in the air. ...and countless sparrows were twittering in the eaves." One would expect a stormy sky, lightning and thunder, but Chopin uses the setting to foreshadow the freedom that Louise feels at her husband's death.
As she continues to think about her husband, Chopin writes that "There was something coming to her and she was waiting for it, fearfully. What was it?" This foreshadows the feeling of elation that she will feel at her husband's death; a fearful emotion because of how inappropriate it is, yet how wonderful freedom feels to her. From here on out, the theme is obvious as Louise basks in feeling "Free! Body and soul free!"
If you find a different theme to be more prominent, different clues will apply. But I hope this can get you started!