This technique to help combat stress and anxiety is from Dr. Mark Hyman from his book, The UltraMind Solution:
Step 1. Put your hand on your belly and allow your abdomen to relax.
Step 2. Close your eyes or soften your focus and look at the floor a few feet in front of you.
Step 3. Inhale through your nose and exhale through your mouth.
Step 4. Breathe deeply into your abdomen and feel it expand as you count to 5.
Step 5. Pause for a count of 1.
Step 6. Exhale slowly to a count of 5, allowing your body to relax and release tension.
Step 7. Repeat for 5 breaths or until you feel relaxed.
Set an alarm on your phone to do this five times a day, every day—upon waking, before every meal, and before you go to bed.