What's the best way to stop your partner from snoring like a bellowing elephant with indigestion ?

You make a pocket on the back of their sleepwear. In the middle of the back. Then you place a tennis ball in it. The person cannot sleep on their back this way. They turn. Problem solved. Oh, a practical method is to get them evaluated for conditions such as sleep apnea, etc. Then one can solve that. Scientifically.