You should change to the No.10 bus.

You should change to the No.10 bus.
You should change to the No.10 bus.

You should change to the No.10 bus.
change本身就有换乘的意思,介词to在这里指换乘的对象.
如：I changed bus at stanford bridge.我在斯坦福桥换了巴士,这里没有指明对象,只用change就好了.

你应该换乘10路公交车

你应该换乘十路车

你应该换十号巴士.