I m going travelling to Jiuzhaigou valley on 25th - 28th July

The weather is changeable during that time and there will be large temperature gap, with the temp range of 18-30℃. So I suggest you prepare summer clothes and light jacket and jeans for yourself and one or two pieces of light gear for your baby as well as relatively thick onesies! As well, it may suddenly rain then, so you also need simple rainy gear.

If you will only travel with your baby, it may be a little hard to handle. Think twice about it or at least, you need another adult companion.