By default our servers will set up your DNS records to point all services (www/ftp/dns/mail) at your hosting account with us.
If you wish to use a different provider for one or more services, or to add a custom hostname to your domain's DNS records, you can do so from within your cPanel account.
In order to update your DNS records you will first need to login to your hosting Control Panel via the Client Management Portal.

Once logged in you will want to select the 'Advanced DNS Zone Editor' option which can be found under the 'Domains' heading.

Select the domain you want to edit the DNS records for, and then you'll be able to edit the records for a domain.
If you want to update your MX records, please use the following KB article: How do I update my Domain Names MX Records (cPanel/WHM)
We recommend you make a note of the current records, and then change them as needed. Details of the options you have are explained in our KB Article: Types of DNS record and what they do
Once you have made changes, the DNS zones will reload within ~5 minutes, but it may take longer before your computer will use the new records due to DNS caching. Please allow up to 12 hours for the changes to fully propagate.
If you have any issues updating / changing your DNS records then please create a support ticket via your Client Management Portal.