This asana is also known as Ardha Chakrasana. The bend from the waist sideways looks like half wheel, that's why it is called as Ardha Chakrasana.

Stand straight with your arms by your side. Breathe normally.  Keep your back and neck straight. Look ahead. Inale and slowly raise you left hand straight up above your head.

Keep your left arm close to your ear. Exhale and bend to your right. Slide your right hand down,

a longside your right leg. Let your left arm touch your left ear as you bendyour head to the right. 

Hold the pose for 10-30 seconds.

Benefits:
This exercise clears blockages in the lungs and improves breathing.  Flexibility of the hips is
improved.  Reduces fat.  It tones the waist.  It will help those who are suffering from back pain,
stiff back etc.  It promotes the functioning of the liver and cures liver problems.