> It sounds silly but try sleeping with tape over your mouth to encourage nose breathing. If you do have sleep apnea, while not as effective as a CPAP machine, it might help. Good luck!

It sounds silly because it is siily

OSA generally manifests itself in the throat/trachea and (shocking, I know) all respiration, whether through the nose or mouth must pass through that area. If that area is obstructed, then it doesn't matter whether you breathe through your nose or mouth (in fact, CPAP masks come in a variety of flavors -- nose only, mouth only and mouth/nose).

I'm not trying to be dismissive here, but given the way OSA causes problems in breathing, your "advice" is worse than useless.