Act as an experienced SEO specialist with 10+ years of expertise in directory optimization. Provide a comprehensive guide on best practices for optimizing directories for SEO, focusing on [TARGET INDUSTRY] directories. Include actionable steps such as structuring URLs for clarity, using [KEYWORD STRATEGY] effectively, and ensuring mobile-friendliness. Also, address common pitfalls like duplicate content and poor internal linking. Tailor your advice for directories with [SPECIFIC PLATFORM] limitations. Use real-world examples and data-driven insights to support your recommendations.