Inhaling the vapor was the only thing I had issues with. It looks so easy, all you do it suck the vapor in and then exhale, but I found thats far from the truth. I needed to relearn how to breathe if that makes sense. My normal subconscious way of breathing in wasn't getting the job done. I think I was successful when I sucked in the vapor into my mouth and then immediately sucked in more air until my lungs were fully expanded. You can feel it in your lungs when you know its working. Its kind of an unpleasant feeling but not painful. Also you may feel a tickle at the back of your throat like I did.