When you feel anxious can you feel your heart more? Can you feel your shoulders tighten? Your neck? Chest opening postures are wonderful to release all the tension that we carry on our shoulders and hold heavy in our heart.
In cross legged sitting, or with your legs out straight, with your back resting against a wall. Find your fingers, cross them and place your hands behind your head. Slightly look up and lift your sternum to open up your chest. Take 5 deep breaths or whatever suits you. Take a rest and go back to it when you feel you need further release.
This exercise is also performing an empowering posture. Do you remember some of the Greek sculptures, when women/men put their hands behind their head? It is a sign of Power and beauty. Show off your beauty and show up for you.