Begin with watching someone breathe while on their belly. The breath should begin in the low back and move upward to the mid back. If it begins in the mid or upper back this is a sure sign of disordered breathing.

The lungs at the left and (B) are inside the ribcage shown as white on blue background.

Enlarged picture of lungs (B).

There is a pattern in much of healthy breathing that relates to the timing of the inhale, exhale and pause. 
Pauses are the time at the bottom of the exhale where no in breath or exhale is occurring.

The above animation might be what you could have while sitting at a computer or desk writing a poem or the copy you are reading, or meditating. Unhurried, safe and comfortably warm.  Or at least when lying down when you are supposed to be in a position conducive of deep rest.  If it does not approach this pattern while sitting, I suspect you have an environmental, biochemical, or mechanical breathing issue. 

It is not to say that if you do not have this pattern that you are not healthy.  From MY view It DOES say that if you DO have this pattern, or even a slower one with longer pauses and less breaths per minute, that from a breathing perspective, the odds are that you are much healthier and/or resistant to illness than one who has a faster breath rate per minute and shorter breathing pauses.  

The development of the breath will cause the breathing cycle to slow.  Simply stated, as the breath gets deeper, it takes longer to finish its cycle.

An eight second breathing cycle is good.  That's approximately 7-8 breaths per minute.  But the pause length is critical.  The pause is the resting phase. It is where the body gets a moments respite.  Shortened pauses mean shortened or non-existent rests.  

So if you have an 8 second breath per minute count you should have approximately 2-3 second pauses. If you have a less than a two second pause it often means that you are breathing what I call tentatively.  Kind of like waiting for the other shoe to drop. Another word I use is "hyper-vigilant".   

You can watch the above animation and see how close to it you are.  Again, the above is not supposed to be perfect.  No breathing is.  But the speed and implied depth by the breath rate and pause length give me significant positive or negative feedback that guide me in my teaching, therapy and training. 

Overall, at rest, slower is better, though repetitive excessively long pauses can be an indicator of snoring, or sleep disorders like sleep apnea.  

In a very deep state of relaxation I have reached 15 second pauses and about three breaths per minute. It was wonderful. Again, pauses are uncontrolled resting phases.  Generally, the shorter the pauses and faster the breath rate, the more the body is being stressed. 

Of course if you eat junk food and tank up on excessive sugar, devitalized foods, fats and alcohol, slay dragons 18 hours a day, you can throw all this off considerably but at least you will be benefiting from bigger, easier, deeper breathing that will significantly offset some or all of those abuses. 

I use the above and many other insights to assess people's breathing.  Some of these insights are in the Breathing Tests and answers. Many more are in the Secrets of Optimal Natural Breathing manual and recorded exercises.

The animation by the way, is not exactly as it should be to discourage copying.  Once you have the manual you can access the proper URL and see the corrected version.   Meanwhile the basic action is good and you may well learn something valuable from it such as the fellow below.

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