How to add a subdomain for emails

Hello,

I currently only have ‘domain.tld’, now I want also to use ‘sub.domain.tld’ so that ‘test@sub.domain.tld’ can be used.

What is the best way to proceed and what DNS settings have to be made there?

Thanks in advance.

I answered it myself 🙂

But now I have 2 MX entries in the DNS for the domain and for subdomain both with priority 10.

Can I leave both at 10 or do I have to set one of them lower?

Thanks in advance.