Discover <a href=https://npprteam.shop/en/articles/facebook/facebook-lookalike-audiences-in-2026-setup-and-optimization/>how to optimize lookalike audience targeting without wasted spend</a> through strategic audience sizing and refinement techniques. Many advertisers create lookalikes once and leave them untouched, missing critical optimization opportunities that emerged in Meta's 2026 algorithm updates. The playbook covers percentage-based lookalike tiers, custom exclusion rules to prevent overlap with existing customers, and retention metrics that signal audience fatigue. You'll understand when to refresh seed audiences, how to A/B test lookalike quality tiers, and which performance indicators demand immediate adjustments. Media buyers applying these methods consistently report 15-25% improvements in ROAS while reducing cost per acquisition.