How do I handle building a new WP website on a new web host when the domain name needs to still poin

Hello, I would like some advice. I am redesigning a client's website and I would like to keep the old site still live while I build the new WP website on a new server. Since the domain name is pointing to the old server and I can't point it to the new web host yet, how do I build the new WP website on the new web host if I cannot move the domain name yet? What is the best way to handle something like this. Has anyone else encountered this? Any tips would be greatly appreciated.

Thank you very much!
Cecilia