Style Generated Xml with xslt

I want to style my xml which is generated by the XML_Serializer http://ift.tt/1t6cdj0

The closer result i can have is to view the xml by: echo htmlspecialchars($Serializer3->getSerializedData());

In other occasions that i have an original .xml file i usually use js: xml = loadXMLDoc("example.xml"); xsl = loadXMLDoc("example.xsl");

but now i do not have a real file.

I can not manage to find an answer as long as this is my first time doing such a thing. Thank you.