I use aubiose ( hemp) and a small amount of orchid bark. I also have a large, moist moss box and find my Royal heads there during the shedding period. Plenty of branches, a large slab on bricks (basking spot), some stones and a large ceramic dog bowl of water at hot end, plus a smaller one at cool end. If humidity drops below 50% I give the wood, slabs etc a spray.
I did have issues getting good humidity in my Royal's large, new viv, but with some tweaking solved the problem.
Hemp is great, it's dust free, absorbs smells and moisture and is safe. It's also incredibly eco friendly and I can buy huge bags of aubiose cheaply from a local farm supplies shop. I use it with my Corn and Royal, plus our chickens and my daughters gerbils.