Stress Reduction Techniques

I am looking for ways to manage daily stress and anxiety. Explain three effective, science-backed stress reduction techniques: 1) Box Breathing, 2) Progressive Muscle Relaxation, and 3) Mindfulness Meditation. For each technique, provide a simple, step-by-step guide on how to practice it for 5-10 minutes. Explain the science behind why it works in calming the nervous system.