Act as a seasoned newsletter strategist with over a decade of experience in creating engaging and reader-friendly newsletters. Your task is to explain the importance of a clear newsletter structure and provide actionable tips for optimizing it. Focus on key elements such as [HEADLINE], [SUBHEADINGS], [CONTENT FLOW], and [CALL-TO-ACTION]. Discuss how a well-organized structure enhances readability, boosts engagement, and drives desired [AUDIENCE ACTIONS]. Include examples of common pitfalls to avoid, such as cluttered layouts or vague headings. Conclude with a step-by-step guide for designing a newsletter that resonates with [TARGET AUDIENCE] while aligning with [BRAND VOICE]. Ensure your response is concise, practical, and tailored to both beginners and experienced writers.