1. Log in to your HostGator cPanel. This is done by typing in your URL associated with your HostGator account followed by '/cpanel' such as www.mysite.com/cpanel and entering in your user name and password.
2. Click the 'File Manager' icon on your cPanel main screen and select that you want to open 'web root.' Check the box beside 'show hidden files' to make all files and folders visible.
3. Click on the 'New Folder' button located at the top of the page. Type in a name for the folder, which should be the name of your subdirectory. Once you have entered in the name, click on 'create new folder' and the subdirectory is created on your HostGator account.