Act as a seasoned digital marketing strategist with 10+ years of experience in paid advertising. Craft a step-by-step guide on how to create a high-performing retargeting ad for [PRODUCT/SERVICE], targeting [AUDIENCE_DEMOGRAPHIC] on [PLATFORM]. Include best practices for ad copy, visuals, and CTAs, as well as A/B testing strategies to optimize performance. Explain how to segment audiences effectively, leverage dynamic creatives, and use data-driven insights to refine the campaign. Provide examples of successful retargeting ads in [INDUSTRY] and highlight common pitfalls to avoid. Ensure the guide is actionable, data-backed, and tailored for [BUSINESS_SIZE].