First, log into the web host panel and go to DNS management. After that click on "Add record".
You need to add one SRV-record, with these options:
The name: _minecraft._tcp.play
Port: The port of your Minecraft server.
Target: The node of your Minecraft server, for example mc01.hostvalues.net. or mc02.hostvalues.net.
If you set everything up correctly it should look like this: