T.M.
hi S....as far as breathing goes, it should be more rhythmic.. in the nose for two counts, out of the mouth for two counts. should match your stride... but, not everyone is there right away.
as a beginning runner, you should aim to run for a certain time, say 5 minutes... invest in a heart rate monitor watch. these watches tell you what range your heart rate needs to be in to achieve optimal cardivascular fitness. it prevents you from working too hard and keeps you working smart. you have set ranges for your heart rate, depending on your age,and your monitor alerts you to when you are below the zone, in the zone (using fat for fuel and killing the calories), or above the zone..(working hard and inefficiently, not to metion, anaerobically).
once you determine your ranges, set off running and pay attention to your heart rate. when its starts to get too high, slow it down. never go from running to stopping. always walk first and look for that heart rate to get back down to 65% (hr monitors display your info in percentages and actual numbers...)
in general, aim for time, not distance, as time is easier to calculate. every day go further, even if it is just one minute. soon you will be going farther faster. running is a gradual accomplishment. you dont want to start out too ambitious and injure yourself. its a commitment and its worth taking the time to fall in love with!
im a runner (not a fabulous one, but i can do a ten minute mile) and a Spinning instructor, as well as ten years of group exercise instructing...! ask me anything. and if i dont know the answer i will be glad to find it for you!
good luck! theres nothing like a runners high!
T.