Be prepared for bad sleep for a couple of nights.
Breath through your nose, not your mouth. Keep that mouth shut. Relax.
The hardest thing is getting a good mask fit. Too tight and it hurts. Too loose and it leaks.
Your settings probably suck. Get rid of that ramp. Consider decreasing your pressure to a much lower setting and having the ramp off as you get used to it, then slowly increase your pressure to your prescribed pressure. Suboptimal pap management is better than no pap management.