In a collection of stories with multiple worlds, how do you cue your readers as to what world your story takes place?
Let's say I have a collection of short stories, there are 1,000 science fiction short stories, and 400 different worlds. How do you tell your readers in which world your story takes place? Do you tell it at the beginning of the story, in what format? How should the text that cues your readers be formatted? Could you provide some real-life examples or show us how to word or format it by a fictional example?
I thought of:
THE FOLLOWING STORY TAKES PLACE IN GIGANTIA
<story begins>