The clothes you'll want depends on where you will ride. Last year on the way to Spearfish it was 106 degrees when I pulled into Pierre SD on the way out. On the way back I took the scenic route which took me over the Beartooth pass and it was snowing there. And from Red Lodge east it rained hard for 100 miles. Those were the extremes. The high country can be pretty cool in mid summer, and the plains can be real hot with lots of wind and little shade. So you need to be prepared for 100 + degrees on the flats to the 30's in the mountains. The amount of clothes you want to bring will depend on if you want to avoid stopping at a laundry during your trip.
For me, I take one pair of riding pants (Darian), one pair of riding jeans, one pair of regular jeans, one pair of shorts, one riding jacket (Darian), electric vest, sweatshirts, tee shirts, swimming trunks, riding boots, loafing or shower shoes, and hat.
Tent, air matress, sleeping bag, and pillow go in a dry bag on pillion. Clothes, towel, and toiletries go in Ortlieb duffel on pillion (I added a small luggage rack). Camping stuff (like stove, pots, utensils, and new this year a chair) and my tools go in the panniers and just stays there if I camp in a motel. I often put a stretch net over the stuff on the pillion just to have a handy place to stuff something in a hurry without opening something up. ROK straps hold the two bags on the pillion. If the tent is wet I don't put it in the dry bag because it just turns it into a fermentation bag.
At a campsite almost everything comes off the bike. But at a motel I just unhook the ROK straps and carry in the two bags from the pillion and my tank bag. The rest of the stuff stays in the panniers. That's the distinction I make when packing the bike. I've been trying for years to cut down on what I bring, but I consistently bring too much, while at the same time forgetting something every trip. Planning is good, but obsessing about it takes all the fun out of it.
Try a local overnighter if you've never moto-camped before. It might give you some confidence and ideas.
I can't wait to get going.