My CPAP finally arrived! (So annoying that I can order consumer goods and literally have them delivered same day, but it takes weeks to get medical equipment.)
Any advice for a brand new user? I don’t know if I’ll get it set up for tonight or not until the weekend (tomorrow).
The mask they sent me is the over-the-nose mask. Not sure how I feel about that. Am interested in what kinds of masks people prefer.
Thank you for any and all input!
I would definitely try wearing it for 15min while listening to music or something not at bedtime, before the first time that you use it for sleep. It can be an adjustment!
When you take it off your face it will make a loud sound. If that bothers you, most machines have a button you can tap to turn off the pressure before you take it off your face. This is good to know about in case you need to sneak out of bed without waking someone up 
Also. Seriously, seriously, use distilled water. It’s not worth the risk of infection. We eventually bought a still because I got tired of hauling distilled water from the grocery store.
You’ve got this! Let us know how it goes.
I think the mask you use is dependent on the individual. A lot of people like the under the nose type, but I found I was ripping it off in my sleep!
I had a choice of adding a chin strap or an over nose and mouth mask. I chose the latter because even the chin strap looked like I could take it off in my sleep. The mouth and nose mask has only been removed in my sleep 3 times since May.
I have a big nose and am slightly claustrophobic, so I immediately went up in mask size from what was recommended for me by the sleep nurse. I sleep much better generally, than when I first trialed the under the nose mask, and better than when I trialed the smaller mouth and nose mask.
Everyone is going to be different though. Masks are a very individual thing.
Oh, also, the schedule they give you for parts replacement - if your insurance covers the full cost, fine, but if not, you don’t actually need to replace the parts as often as they claim. If you look at the European or Australian guidelines for the same exact machines and parts, they will often have a replacement cycle of 2x longer for the same things. 
+1 to the tip of trying it before you’re tired and ready to go to bed and don’t have the patience to fiddle with it. If your apnea is that severe, using it for a bit of time in the evening while awake probably also helps with your oxygenation.
My main tip is don’t reject it immediately. If the mask doesn’t feel right, give it a couple of days and if you still hate it, try a different kind. If the air feels too dry/wet, play with the humidity settings.