This place is a painting. Absolutely serene. It is a World Heritage Site and a World Biosphere Reserve. Staying at the nature park overnight is not allowed anymore to reduce polluting the ecosystem. Some people have mentioned that you can persuade someone in the seven Tibetan villages to host you overnight. It's a long shot, but still worth a try. I had no luck with that.
The entrance to the park is expensive, so take your student identification or ask someone who has student identification to buy your ticket for you. Once you enter the park, a bus will take you to the beginning of the trail. You can take buses to different viewing spots after that. I would recommend walking to lose the crowds and actually appreciate the ecology of the place. You might miss a couple of spots this way, but you'll make up for it by walking down the winding roads looking for hidden paths and trails.