To find your brand's content niche, you must first create marketing personas based on your audience segments using demographics and psychographics. Second, create a brand bible that defines your brand story, personality, and values. Third, focus on key performance indicators and metrics to define your goals. Then brainstorm content ideas that match your personas' interests while relating to your brand. Identify the central idea or message of each piece of content while considering your brand's voice and audience. Choose appropriate formats to tell each story and translate it into real-world experiences. Finally, periodically review performance data to ensure your niche evolves with your audience over time.