Setting and Characters
Themes generally relate to human nature or to the individual in his environment. Therefore, considering the story's geographical location, period in history and social setting will be helpful in establishing theme. It's also useful to look at how setting affects the characters in a story. A character's environment and relationships might make her feel trapped, as Louise Mallard does initially in Kate Chopin's "The Story of an Hour." When her environment seems to change drastically with the news of her husband's accident, she experiences joy and freedom.
Plot and Conflict
Plot is generally a reference to a story's organized development and to how events within the story tie together. Typically, a short story is composed of a series of events involving a conflict or problem that is resolved at the end. Ideas, wills or desires clash in some fashion which can be referred to as the conflict, and that conflict might be physical, psychological, moral or emotional. A theme should be an idea that is sentence-length and not merely a word or phrase. For example, the major theme in Stephen Crane's "The Open Boat" is that nature is unpredictable and indifferent to the needs of humans. To state this story's theme as "nature" is too broad.
Symbols and Imagery
Symbols are objects, situations or persons present in a story which also stand for and suggest something beyond their literal meanings. Therefore, they can provide important clues to theme. A rose or roses in a story might suggest love, while a thorn implies love's perils. Imagery is the collection of mental images developed for the reader by the author's use of description. Imagery will frequently appeal to the reader's five senses. Therefore, it's helpful to note how the author's description has stimulated the senses and evoked feelings and reactions, and then to consider how these reactions contribute to the story's overall meaning.
A short story author has something significant to say about the human condition, and uses fictional elements to convey it. How characters are responding to their circumstances mirrors human behavior in real life and provides commentary about our lives. This commentary takes the form of a useful insight about human character, as well as a controlling idea or theme. Paying attention to the story's title and what it suggests can help determine theme. After writing down the generality that is the likely theme, make certain that it actually considers all of the story's events. Although there is no one specific way of stating a theme, the theme can rarely be reduced to a familiar adage or saying.