The first stretch is for your thoracic area. Sitting in a chair that has a medium back height, put your hands behind your head, and lean back over the backrest of the chair. Relax if you can and hold it for 30 seconds; repeat 3 times.
Next, you want to stretch your pectoralis muscles. If you have a foam roll, this will work best for the stretch. Lie down on the foam roll where it is directly on your spine and your head is supported. Now rest your elbows on the floor out to the side. If that is not enough stretch, you can straighten your arms out and rest them on the floor. If that is still not enough stretch, place your hands behind your head, and press your elbows downward. Hold for 30 seconds and do them 3 times.
Now roll onto your stomach. Roll up a towel and place it under your forehead for comfort. Now put your arms straight out to the sides like you are making a T with your body. Gently raise your arms towards the ceiling, and try to squeeze your shoulder blades together. Your arms don't have to go high, but they do need to be controlled. Hold them for about 2-3 seconds and do about 10-15.
Roll back onto your back for "snow angels." This exercise was shown to me from my PT friend Phil who helped me rehab from my shoulder surgery. Put your arms flat on the ground into a slight stop sign position or like you are getting ready to make a snow angel. You can bend your knees your put your legs out straight, but bending the knees will help support your back. Now slowly slide your arms upwards, and try to keep your elbow and arms flat on the ground. Once they start coming up, then slide them back down. You only need to do about 10 of these with 2 sets.
The next stretch is going to be in long sitting where your legs are straight out in front of you. Clasp your hands together directly in front of you, and punch forward while your are curling your back forward and bringing your chin to your chest. You want to have a curl in your back. Hold this for 30 seconds and do 3 times.
The last exercise is "bird dogs." This is done on all fours or in quadruped. Try to keep your back straight like a tabletop, and try to keep your neck in a neutral position so you don't strain anything. Now lift one arm up and bring it straight forward. At the same time, lift the opposite leg straight out. Alternate your arms and legs, doing 5-10 on each side.