The usual routes of visiting Daocheng Yading is either by flight or by car. By flight one can fly from Chengdu, or from Xi'an, Chongqing and Hangzhou. By car you can either do it from Chengdu or from Lijiang/Shangrila.
The drive from Sahngrila/Lijiang to Daocheng Yading takes a little less than 2 days passing by places such as Derong, Xiangcheng. The drive from Chengdu to Yading takes 2 days passing Kangding, Xinduqiao, Litang and Daocheng.
Daocheng Yading usually refers to the tourist park of Yading. Daocheng and Yading are two different places. However, one who goes to Yading will often need to go to Daocheng first when you are traveling from either Shangrila or Chengdu, and when you are either flying or driving. Daocheng is the stopover place for Yading. Daocheng is a town with over 20,000 population with decent hospital and hotels, Yading is a small tourist town with probably around 2000 people.
From Daocheng it is 72km drive to Yading entrance at a place is called Riwa, and now called Shangrila Town or Shangrila Zhen (different from Shangrila, or Shangrila Shi in Yunnan). Riwa and Shangrila Zhen are the same place. Riwa is the entrance of Yading Park. From Riwa one buys the bus ticket and it is another 35km(about 1h) to the actual Yading Park.
To do a middle kora trek of Yading one usually starts from the east of Yading Nature Reserve at a village called Dulu near Shuiluo, one place that has to be accessed from Muli County.
Route: Chengdu - Siguniang - Tagong - Yading - Xinduqiao
Route: Daocheng - Yading - Daocheng
Route: Daocheng - Yading - Daocheng