Leave a polite but cranky note on their door telling them how loudly and badly they’re snoring and how it’s keeping you awake. It might be the thing they need to actually go to a doctor and get their snoring checked out. No doubt their partner or people they share a house with have told them a few million times and been ignored by the snorer each time.
You have my sympathies. I snore and so does my husband. We have diagnosed sleep apnoea. We both use CPAP machines now so there’s barely a snore to be heard now. I’m no longer woken by DH’s snores multiple times each bloody night unless he’s been dumb enough to not put his mask on before going to sleep.
Buttercup: That’s easy: in the next room is worse. You can’t wake them up and tell them to STFU up or try rolling them on their side to lessen the snoring or make them blow their nose to clear any blockages. In the same room you can tell them to stay awake until you’re asleep first so that at least you’ll get some sleep before being woken by their snoring.