In an era of emotionally saturated digital media and information overload, effective communication demands more than clarity and accuracy-it requires emotional awareness. This review introduces the paradigm of emotion-aware design, a framework grounded in the valence-arousal-dominance (VAD) model of affect, which systematically examines how emotional modulation shapes comprehension, memory, and behavior. Drawing on insights from psychology, neuroscience, communication, and design, we show that emotional responses significantly influence how information is perceived, retained, and shared. We further propose a multimodal design space-encompassing text, visuals, audio, and interaction-that enables strategic regulation of emotional dimensions to enhance communication efficacy. By linking emotional dynamics to cognitive outcomes and practical design strategies, this review offers both a conceptual foundation and an applied roadmap for designing emotionally resonant communication across domains such as education, health, media, and public discourse.