In your readings of areas of Mayo Clinic Connect you will hear the words "We are all different.
For myself it has taken me quite a while to understand everything. The key is to learn as you go by finding the information you need and the routine that is best for YOU.
Nebulizing by itself is not Air Way Clearance. There are different things one can do that fall under what Air Way Clearance Techniques are. Autogenic Drainage is one, Active Cycle Breathing is another and Postural Drainage is another. Some people do certain Yoga postions to help with air way clearance, clearing the lungs of the mucus and mucus plugs.
However with Postural Drainage people must be aware of the fact that it is not best for people with Acid Reflux.
As you are probably realizing, much of the information on this thread can be found by searching the internet.
Hope you are finding all you need. There is much on all of this information on other threads on this Mayo Clinic Connect and hope you are able to find them. It does take time and that is a precious commodity.
Barbara