I like to recommend the Breath Mediation:

1st- Take a deep breath and release the air. Fill your longs until no more air can get in. Hold it for 3 seconds and then let it go.
2nd - Visualize a beach, write your name in the wet sand... while you do it, inhale.
3rd- When the waves approach, release the air, softly. Witness how your name is erased. Visualize the sound of the sea.

Repeat this process around 10 times. You breathing will be deep and calm now (like when you are asleep)

I hope it helps!