How should I setup a new user under my reseller plan?

I have a reseller account. Everything works fine with my main domain but now I want to add “clients” and I am not sure what’s the right way to do it. After adding a new user on the panel what else has to be done?
For example…
if my main domain is “root-domain”
and my client’s domain is “client-domain”
do I need to add a MX record in “client-domain” that points to “root-domain”?

Have you read through all of the tutorials here:

https://mxroutehelp.com/

Heya,

You should have gotten an email with the subject “Important Reseller Information”. The DNS records in that email are also valid for your clients.

Thanks! Do I need the TXT record too? And…
Would it be fine to create a redirection from my domain so that the DNS records are customized?

You will need that spf TXT record if you plan to send messages using that domain. A redirection in this case would be a CNAME. Putting a CNAME in an MX record is technically not allowed, but I don’t know of an MTA that doesn’t support it. So that should be fine.