Melissa Mackey presented on using time-based remarketing and fresh, relevant content to engage customers at different stages of their buyer journey. She recommends mapping content like white papers, videos and offers to ad groups based on the time since a user's initial visit. Segmenting audiences based on when users visited and the content they've seen allows targeting them with new, related material to continue engaging them without repetition. Testing different content combinations and measuring performance helps optimize the strategy across channels over time.