How do I create an invisible digital certificate?

 How do I apply an invisible signature to a document?

 By default PDF-XChange Viewer adds text from the certificate into the appearance of the digital certificate and applies it to the document.

The appearance of digital certificate is customizable.  

To customize the appearance of a digital certificate:

1. Import an existing Digital Certificate or create a new one using PDF-XChange Viewer.
2. Customize the appearance of the Certificate.
   1. Select Document --> Signing --> Sign Document
      
      
       
   2. Place the signature on the document where you want it.  The blue bounding box will show where it is to be placed.
      
      
       
   3. In the "Sign Document" window select the signature you wish to use.  Note that it can be either a certificate from a file, a certificate from the Windows System Store or a new certificate that you create using the Viewer.  Select "Manage"
      
      
       
   4. The "Digital Sign Appearance Templates" window opens.  Here you can manage the appearance of your certificates.  You can use a single digital certificate with multiple appearance templates.   This can be used to assign an image to your signature or set it to have no visible attributes.
      
      
      
       
   5. Select the signature you wish to change the appearance of and click "clone".
      
      
       
   6. Select the new template from the list and click Edit.  To have the certificate show nothing on your document uncheck all the options in the "Edit Template of Digital Sign" window, give it a name and click OK.
      
      
       
   7. I called this template "Invisible". 
      
      
      
       
   8. Click " Close" to close the window and exit the Digital Signatures Templates.
       
3. Your new template "Invisible" is now available for use in future by selecting it from the list of templates in the "Sign Document" window when signing documents.
   
   
    
4. Because you can assign an image to the template you can also use a Transparent Signature image of your own hand written signature to be presented in place of the digital one.  Choose "Custom Icon" in the "Edit Template of Digital Sign" step above and browse to your signature image as described in this article on how to create a transparent signature stamp. This results in a digital signature that looks like your signature. 

 Please note!  The laws around using an image as your signature on a document like this vary from place to place.  It may be that in your area to be legally binding a signature it must be hand written in ink.