What's the safest way to rename name servers?

Hello,

What’s the safest way to rename name servers. I have already 5 domains using ns1.old.com ns2.old.com and the domain name old.com is as child-ns.

I want to let expire old.com domain name and want to use new.com. So how to replace these 5 domains to use ns1.new.com and ns2.new.com

Do I need to edit them manualy in dns zones of this 5 domain names?

Thanks!

Yes, at least the NS entries, also edit it on the user packages for future domains. Be sure the new name servers are working properly before you move any other domain.

thank you very much.