[ianai]

For me, it's a combination of always ensuring my sinuses stay open and proper head placement for the mask to stay tight. Google "ayr gel" - I use the gel specifically. In dry periods or for congestion, that seems to (often) be enough to keep my sinuses open. For my current cpap mask I have to lay flat with no pillows for a proper fit. Then there's all the sleep hygiene stuff - no lights, proper bedroom temperature (cold), etc. (No lights means no lights - not even reflections from hall lights or the indicator lights from electronics can be tolerated.)