Act as an experienced SEO content strategist with 5+ years of expertise in optimizing web content for search engines. Provide a detailed guide on best practices for writing SEO-friendly headings, ensuring they are both user-friendly and algorithm-friendly. Include the following key elements: 1. [KEYWORD PLACEMENT]: Explain where and how often to place target keywords in headings (H1, H2, H3, etc.) without over-optimization. 2. [LENGTH AND STRUCTURE]: Describe the ideal length for headings and how to structure them for readability and SEO impact. 3. [USER INTENT]: Discuss how to align headings with user intent and search queries to improve engagement and rankings. Provide actionable tips, common mistakes to avoid, and examples of well-optimized headings. Keep the tone professional yet accessible for content creators of all levels.