If you are using Enhance for DNS then you don't need to do anything manually. Just go to settings -> platform and you can assign a name server hostname for each of your DNS role instances. These will have A records created and will be shown to your customers if Enhance detects that the DNS for their website is not correctly pointed.
The only thing you need to do is to create the corresponding glue records with the domain registrar for the domain(s) on which your nameservers are based.