Take the first line, sentence, or paragraph of a piece of writing and create your own story from it. You should acknowledge the authorship of the inspiring piece somehow. Otherwise, write it as you wish. This exercise is most interesting if you use a first sentence from a text you haven't read yet. Read the parent text afterwards and compare.
My parent text is "Trespass," a short story by Julia Alvarez, published in How the García Girls Lost Their Accents.
"The day the Garcias were one American year old, they had a celebration at dinner."
The original story is 81 paragraphs long. Likely my piece will not be as long. Stay tuned for it.