Kurt Vonnegut Jr. was an American author, satirist, and graphic artist known for his darkly humorous and satirical novels that blended science fiction, black comedy, and satire. His work included 14 novels, 5 plays, 3 short story collections, and 5 nonfiction works published over 50 years. Vonnegut's unique perspective and writing style influenced generations of writers and redefined writing itself.

(As published in the introduction to his 1999 short story collection)
Bagombo Snuff Box: Uncollected Short Fiction
They are intended to provide structure and guidance for aspiring fiction writers.
Here are Kurt Vonnegut's 8 rules for writing a short story:
Bagombo Snuff Box is a 1999 collection of 23 previously uncollected short stories by Kurt Vonnegut, Jr., originally published in magazines like Collier's and The Saturday Evening Post between 1950 and 1963. The book includes an introduction and a concluding essay by Vonnegut, who also revised three of the stories for this collection, offering a humorous and poignant look at post-war American life through his developing style.
23 short stories, many from the 1950s, that were not included in his earlier collection Welcome to the Monkey House.
Explores American life with characters like salesmen, housewives, and soldiers, often reflecting Vonnegut's experiences and early career.
Features an introduction and a final essay, "Coda to My Career as a Writer for Periodicals," where he reflects on his work.
Vonnegut rewrote the endings for three stories: "The Powder-Blue Dragon," "The Boy Who Hated Girls," and "Hal Irwin's Magic Lamp".
Published by G. P. Putnam's Sons in 1999, it was his first collection of these specific stories in book form.
Further Reading: wikipedia.org/wiki/Kurt_Vonnegut