Congrats on your new camper and welcome to the forums!
I would add to the advice above:
- Have at least two lengths of sewer hose and fittings.
- Keep at least 50 ft of potable water hose.
- Keep a utility hose (separate from your potable water hose) for rinsing your sewer hoses, cleanup around the camper, etc.
- Get a 30A to 50A adapter in case you are in a campground with 50A only. (I've run into that before.)
- You'll need several odds and ends pieces of boards or a pack of Lynx Levelers for leveling your rig at the campsite. I like the Lynx Levelers just because of ease of storage.
- Keep plenty of sewer drop-ins or bottles of sewer treatment and RV toilet paper on hand. Trust me, the better job you do rinsing and treating your black and gray water tanks, the happier your camping experience will be. I learned this the hard way with my first camper. I have tornado type rinse systems in both of my black tanks on my current camper, but you can get a decent rinse filling and dumping.
- Make sure you got wheel chocks of some type. I recommend the X-chocks, they're the bomb. But, any type of chock will work fine. Make sure you have the thing level and chocked before you unhook from your tow vehicle.
You'll learn a little more each time you take it out. Like the poster above said, don't be afraid to ask other campers for advice at the campground. Trust me, we RVers love to talk and help one another out.
Good luck, and hope you have many wonderful years of camping!