1) The document provides optimization strategies and best practices for Google Display Network campaigns. It outlines five example use cases and provides tips for each on how to optimize campaigns to meet specific goals like getting started, increasing conversions, optimizing ROI, and increasing volume.
2) For campaigns aiming to increase conversions of existing site visitors, it recommends setting up remarketing campaigns with lists targeting different visitor types and tailoring ads and bids to each list.
3) For optimizing campaign ROI, it suggests lowering bids on poorly performing keywords/placements, expanding what works, and using conversion optimizer once thresholds are met.