Using mouth tape can improve deep sleep by promoting nasal breathing, reducing snoring, and enhancing oxygen intake. Mouth tape keeps the mouth closed, preventing dry mouth and encouraging proper breathing, while nasal strips open the nasal passages, improving airflow and reducing congestion. Together, they help facilitate better restorative sleep. It's important to use hypoallergenic products, avoid these methods if you have nasal blockages or sleep apnea without consulting a doctor, and start gradually for comfort and effectiveness.