If you want to expose RDF data for Piggy Bank to collect, add one or more links to RDF/XML or RDF/N3 files in the <head> element of your web page like this:

 <html>
   <head>
     ...
     <link rel="alternate" type="application/n3" title="Screen scrapers' information" 
       href="http://people.csail.mit.edu/dfhuynh/research/downloads/screen-scrapers/screen-scrapers.n3">
     
     <link rel="alternate" type="application/rdf+xml" title="My contact information" 
       href="http://people.csail.mit.edu/dfhuynh/foaf.rdf">
     ...
   </head>
   ...
 </html>

Note that the URLs to your RDF files must be absolute.