The best way to improve ROAS on Meta for a Shopify brand is to work through four levers in order: fix tracking accuracy first, since optimization built on bad data compounds the problem; improve creative testing velocity, since creative is the single largest driver of Meta performance variance; clean up audience and campaign structure to stop budget fragmentation; and only then adjust bids and budgets, since bid changes on a broken foundation produce unreliable results. Most founders jump straight to budget and bid adjustments because they feel like the most direct lever, but they are actually the least effective fix when the underlying tracking or creative is the real constraint. This guide works through all four levers in the order that actually moves ROAS, not the order that feels most intuitive.