October 2025 My Bestseller -- Publishing AI Era Writing Formula 3GO, October That Started with Excitement and Ended with Gratitude: October 2025 is special for me. This essay reflects on the experience of publishing the book AI Era Writing Formula 3GO and the emotions of seeing it become a bestseller. The author reflects on the journey from beginning to write about AI-era writing skills to completing and publishing a book -- the vulnerability of putting creative and intellectual work into public view; the unexpected response as the book found its audience; gratitude toward readers who engaged with the ideas; the October atmosphere (the Korean autumn, the poet Kim Dong-gyu song about October referenced in the essay) providing a backdrop for reflection on how achievements that seemed impossible become real through consistent effort. The 3GO writing formula: the book teaches specific methods for human-AI collaborative writing that preserve the authors voice while leveraging AI productivity; the October bestseller status validates that there is significant reader demand for practical guidance on AI-assisted writing.