You can stop your dog from barking a lot by determining the triggering cause or the external stimulus. Some of these stimuli include, improper confinement, separation anxiety and environmental sounds. It can also be due to fear or territorial behavior. You can try to remove the stimuli or use behavioral modification. Go to http://www.usask.ca/wcvm/herdmed/applied-ethology/behaviourproblems/barking.html for more.