http://youtu.be/d7deT0oBMzo
9/11 breathing.
Breath in for a count of 9 and out for a count of 11.
Essentially the out breath is longer than the in breath.
When you breath in, the sympathetic nervous system is excited. This is the flight of fight response.
When you breath out, the parasympathetic nervous system is engaged. This takes you down and is relaxing. You will be able to think more clearly.