first, you go to your cpanel, log in, and go to the front page, and click on the subdomain icon.
this takes you to the control page for subdomains, listing any you have already created.
at the bottom is the new subdomain creation box.
to add a new subdomain, enter the name you want to add into the text box i have circled for you in the following pic, and then
from the drop down menu, select which of the domains you want the new sub domain to be created under, and yes, you can create a sub domain of a subdomain.. i have one created called http://puff.puff.pass.nbkillas.net where my main domain is http://nbkillas.net .
for this example, i will create a test subdomain under another sub so when it is done, i will have a new subdomain called http://test.wh0r3.nbkillas.net .
when you finish sucessfully, you will see this:
AND when you go to your file manager, or ftp, you will see the newly created subdomain as a new folder right where you told it to create it, be that on the root of your public_html folder, or on the root of a current subdomain that you created.
hope this helps!
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