Many ways. It depends upon who you are speaking to. [Since APPARENTLY Mr. Formality over here generally greets people by their name whenever he can be bothered to greet anyone in the first place, smdh. But I was told "ni hao" is still fine so he will write that.

Fortunately Lan Wangji is not the only cultivator here, so!!] Wang-gongzi should be able to understand, if the message is properly conveyed.