Since sometime close to forever, the way to preview sites prior to pointing DNS, was to modify the hosts file on your PC. If you’re not familiar with the hosts file, it’s a file on your computer that allows you to take advantage of the DNS lookup hierarchy. Modifying it allows you to view a website on a server that hasn’t had the domain name pointed at it yet. It’s a great trick for previewing sites, but it’s not without drawbacks. Mainly, you’ll need to remember to un-modify it. And for some reason, modifying my hosts file doesn’t work for me anymore.
Then we found https://hosts.cx/ and viewing un-launched sites became much easier. Just enter the IP address and the domain name of the domain name of the site and click Get My Testing URL.
This takes you to page with a link to your temporary site for viewing. Plus there’s a QR code you can point and click at from your mobile phone to preview the mobile version of your site too. They did their homework!