Learning how to breathe (inhale and exhale) properly has benefits such as improving a runners performance.
A good description of a breathing technique on how to breathe and boost performance is from Military.com
Many experts will say that to fully oxygenate the muscles and clear the body of carbon dioxide you should breathe a 3:2 inhale-to-exhale ratio; full inhales and full exhales. This means you INHALE on the LEFT, RIGHT, LEFT foot strikes and EXHALE fully on the RIGHT, LEFT foot strikes. This pattern is not that hard to turn into a habit, but it may require you to slow your pace down for a few runs to master the technique. You will notice a lower heart rate as you are able to get more oxygen in and more importantly push all the carbon dioxide out of your body. You may notice that you naturally drop to a 2:1 ratio when you are really pushing it to the finish. That is OK. But realize it is difficult to maintain a pace that requires you to breathe at a 2:1 ratio.
There are many techniques on how to breathe, the best way to find a method that works for you is to try them all. If a method you tried does not work, try another method, when you find a method that works stick to it.
The following breathing tips have worked for me.
Breath more from your diaphragm (belly) than your chest (chest breathing is more shallow).
Focus on exhaling more fully. This will remove more CO2 (Carbon Dioxide) and allow for deeper inhalations of O2 (Oxygen), I do this when I reach a hill and slow my pace.