I'm going to travel to Jiuzhaigou immediately, from September 6 to 9, from September 7 to Jiuzhaigou and from September 8 to Huanglong. What should I pay attention to? How many clothes should I wear?

We just got back from Jiuzhaigou on August 23rd. It is very cold at night and when it rains. We need to wear wool. We think it's not too much to see someone wearing a thin down jacket. We'd better wear hiking shoes, mainly because some places are slippery. On sunny days, it is necessary to wear short-sleeved shorts and sun protection caps. In short, we must carry a big package to cope with the weather change. It's pitiful to see that many people wear less clothes and have to buy big shawls packed in tourist shops. This is a tourist attraction. There are scenic buses and plank roads all the way, and the facilities are very perfect, which is not much different from the intensity of playing in urban parks such as the Summer Palace. On the whole, this is a huge park. If you climb slowly from a low altitude to Jiuzhaigou, which is more than 3,000 meters, as long as the activities are not intense and you are not in a hurry, there will generally be no altitude sickness. There are also many children and old people among the dense tourists, and they are in good condition.