Stories, when they come to me, begin with a person.
Not a plot, and rarely a world. A character simply appears, sometimes only a vague figure at first, sometimes already vivid enough that I know how they move through a room or the tone of their voice when they speak. They usually arrive without explanation, and I rarely go looking for them.
Once they appear, they begin to gather details. A name comes first. Then a temperament, small habits, the kinds of things they notice and the kinds of things they avoid. Gradually they become more defined.
After that, I begin to wonder where they belong.