Deliberate regulation of diaphragmatic breathing can contribute to well-being. We present a targeted-heat wearable designed to direct attention inward during breathing practice. In a mixed-methods study, breathing was guided with a pulsing-heat or a screen-based app. We included physiological measures of heart-rate, HRV, and breathing pace; self-report questionnaires on interoception and mindfulness; and qualitative interviews. Results show both groups adhered well to the breathing guidance, yet heat-condition participants reached lower heart-rate and reduced sympathetic activation, physiological markers associated with stress reduction. They also reported higher interoceptive awareness, specifically self-regulation and body-listening abilities, alongside significantly higher state mindfulness. Qualitative findings revealed that targeted-heat fostered a stronger connection with bodily sensations and emotions, while visual feedback was often experienced as pulling attention outward. Our work suggests that breathing with the heat wearable increases the known positive outcomes of diaphragmatic breathing, helping people connect more deeply with their bodies by directing attention inward.