I use a gel mask with my humidifier CPAP and it has a twirling thing on it that spins 360 degrees. I sleep all over the place side, belly and back. I couldn't imagine sleeping without it.
I am a mouth breather and I use a nose mask. Make sure you have a humidifier and you'll be ok. Also, get a prescription for a sleeping pill. You can't do without your CPAP or you'll risk a stroke or worse.