Add your own branded sending domain - DNS record issue

I'm in the process of creating my own branded sending domain to comply with Google and Yahoo's new sender requirements. 

I normally send all my email with myname@mywebsite.com so I went it to DNS records to add the dynamic records from klaviyo. When doing so my DNS management system asks the following when adding ns1.klaviyo.com:

Please add a period symbol at the end of the domain name if the domain should NOT be auto-appended with .mywebsite.com

So my question would be; should the result be: ns1.klaviyo.com.mywebsite.com 
OR should I add a period at the end of the value ns1.klaviyo.com so it doesn't add mywebsite.com at the end of the value.

Klaviyo chat support wasn't able to help me so they've escalated it, but in the meantime, I'd love to fix this asap. 

Thanks!

Rianne