But once the fantasy is over and my consciousness returns to normal, I know I've been dreaming. When I return to full consciousness, I may still be out of my body. Of course, I only say that after I examine my state of consciousness and detect that I am fully aware during the experience. That way, I leave no doubts that I was conscious at the time, and not involved in a dream-fantasy. Famous OBE researcher Robert Crookall devoted a book to the subject, called Psychic Breathing.
Breathing exercises have many benefits.
Breathing exercises, if done correctly, can bring you energy that may prolong the experience. Also, it can improve your ability to focus. I recommend doing breathing exercises before you try to induce an OBE, and not during the induction. Here are some pointers for your breathing exercises. Babies breathe naturally because they haven't learned our bad habits.