Since I'm not familiar with your domain name provider I can only give you a basic idea of how to go about it. You should be able to login to your account at your domain name provider and see an option, should be form fields that have ns1: and ns2: beside them. Just type in the heliohosts nameservers in those fields. If ypu don't see any options like that then contact your domain name provider and ask them to do it for you.
To be honest I really don't understand all of the technical aspects of DNS and my attempt at explaining it might be a little off, but I'll be glad to Google that for you.