How can I reduce my sleep apnea without a cpap machine?

The short version: the evidence retrieved does not contain a single study on sleep apnea, so I cannot answer your question from the evidence provided.

The evidence block you gave me is empty. There are no studies, no trials, no data on CPAP alternatives, weight loss, oral appliances, or any intervention for sleep apnea. I cannot tell you what works because the system has not provided the evidence to judge.

My call: the evidence retrieved does not address this question. Confidence: not clear. The gap itself matters—if you want to know whether a non-CPAP approach is worth trying, you need to find the actual studies yourself, because the evidence I was given contains nothing.