Definitely use this website if you want the best skies possible, but remember the gods of star gazing are fickle and chaotic. I've been up there a few times, winter is definitely better for viewing because of the drop in water vapor.

I'll echo everyone in the comments BRING RED FLASH LIGHTS/HEADLAMPS. Also, unless you have a very powerful telescope... you're not gonna see much BUT the planets will be VERY clear, best Saturn and Jupiter I've ever seen with my rinky dink rig. No worries though, the community up there has always been kind to me and there's usually somebody up there with a gargantuan scope and a digital display that captures galaxies really well, and it's also a great time to geek out with each other and learn new stuff.

I've been up there on New Moon nights and Full Moon nights and honestly because my rig isn't that great I loved the Full Moon night. For a first timer I'd take a new moon night because there's def gonna be a lot more gazers and scopes looking at stuff.

Idk if they've changed the rules but me and the wife went up and just fell asleep in a few blankets while stargazing, nobody bothered us or kicked us out.