Using WHM you can create a new SSL certificate and install it. There are a few "tricks" that may not be obvious the first time you do this.
On the left hand side bar in WHM, find the section for "Web SSL/TLS", and click on "Generate a SSL Cert....".
Enter the information. If you enter a password you will generate an encrypted certificate.
People have reported that both unencrypted and encrypted certificates work.
You are generating what is called a self signed cert. You don't have to go buy one if you don't want or need to.
Now click "create" and the certificate is created. You should copy/paste the information into a text file on your local computer for reference.
NOTE: It is also saved on the server when you create it.
You want to copy the whole thing, this is how you will copy/paste it anytime you need to do it manually.
You need both the certificate (.crt) and key (.key) files to install a certificate.
Next, in your WHM the next thing down is "Install a SSL Cert....", click on that.
If all that doesn't work, you have to manually copy/paste the cert info into the boxes. I found that if I typed the wrong thing into the domain box then it would not find the cert so make sure you have typed it the same as on the cert. If you have several certs already created on the box you will have to be more specific about the domain name.
If you do manually enter the info, make sure you have the 5 dashes to either side of the BEGIN CERTIFICATE and END CERTIFICATE and that no white space, extra line breaks or additional characters have been inadvertently added.
After that just click "do it" and it will install the cert for you and restart SSL/Apache
Try a SSL connection and see what you get
Note: You need a dedicated IP for each cert generated. Your virtual users can use your "shared" cert from your box for their sites.