Act as an experienced SEO content writer with 5+ years of expertise in crafting high-converting testimonials. Your task is to create a step-by-step guide on writing SEO-friendly testimonials that boost credibility and search rankings. Focus on [TARGET KEYWORD INTEGRATION], [STRUCTURE FOR READABILITY], and [AUTHENTICITY TECHNIQUES]. Include examples of before/after optimization for [E-COMMERCE PRODUCTS], [SERVICE BUSINESSES], and [B2B SOFTWARE]. Explain how to balance persuasive language with natural keyword placement, and highlight common mistakes like [OVERLY GENERIC PHRASES] or [MISSING SCHEMA MARKUP]. Provide actionable tips for collecting and polishing raw customer feedback into compelling, search-optimized content.