three simple but effective asanas:

Yogamudra

Sit cross-legged (sit in Padmasana, Ardha padmasana orVajrasana  ). Hold your left wrist with your right hand behind your back. Slowly lowering your chin, then your neck, bend down as far as you can go, breathing out as you go down. Stay there for 8 seconds with your breath held out then rise up, breathing in. Practice eight times.

Cobra  (Bhujangasana)

Lie down on your stomach. Put your hands facing down on the floor beside your ears. Supporting your weight on your palms, push up and raise the chest, looking up towards the ceiling. Breathe in while rising, and hold your breath in that position for 8 seconds. Come down to original position while breathing out. Practice eight times. 

Long Salutation

Kneel down with your buttocks resting on your heels and your toes pointing forward. With your palms together, extend your arms up next to your ears. Slowly bring your arms and head down as one, first bending your neck then the whole upper body, until your fingers hit the floor, keeping your buttocks on your heels all the time. Now stretch out along with your forehead and nose resting on the floor. Breathe out as you go down and stay there with your breath held out for 8 seconds. Then rise up, breathing in. Practice eight times.

and remember: keep breathing, breathe, relax, relax and relax to the max! 

Savasana

Lie on back with arms by the side, inside of hands facing up, make sure that the breathing is calm and relaxed, watch the air flow through the nostrils, throat, into the lungs, the belly, the diaphragm expands, slowly, ever further, the belly, the chest slowly filling the lungs and reverse - exhale, slowly, let the air flow gently back out. 

relax...

Now go through the whole body, starting at the tips of the toes feet, consciously making sure that each part is completely relaxed – with no muscular tension at all.

From the feet up, chins, calves, the legs, thighs, consciously checking each part, into the groin area, into the abdomen (also feeling the internal organs are relaxing), into the chest and shoulders, from the fingers and hands up the arms, then into the neck and up into the face, relaxing the facial muscles, nose, lips, mouth, tongue, ears, including the eyes, forehead, and finally to the top of the head, the brain is relaxed. 

Check once more that the breath is calmly, just floating and relaxed, imagine floating on top of the sea, suspended in space, on top of a mountain, imagine a sunflower or poppy field – whatever seems attractive or comes by itself - float. Now stay like that, fully relaxed, for a few more minutes....forget time, forget it all immerse into the ONE and ALL - float, let go...