Point your browser at https://manage.liquidweb.com/ and log in with your user ID and password.
Once you are logged in click on the Domains link in the left sidebar:
Then click on the DNS tab:
At the bottom of the page will be a Reverse DNS header. Select the server you wish to set reverse DNS for from the drop down menu:
Then click on Add next to the IP for which you’d like to add Reverse DNS:
Put the hostname in the box next to the server’s IP. Then click the green checkbox:
At this point you’ll receive a verification message. If everything looks correct, click on Set Reverse DNS:
You’ll then receive a notification that your changes were saved: