Create Custom PDF

Sample UI Action

var text = current.getValue('description');
var htmlDescription = text.replace(/\n/g, '<br/>');

var html = '<h1>' + current.number + " - " + current.short_description + '</h1><h2 style="color: #5e9ca0;"><span style="color: #000000;">Description:</span></h2><p>' + htmlDescription + '</p>';

new sn_pdfgeneratorutils.PDFGenerationAPI().convertToPDF(html, current.sys_class_name , current.sys_id, current.number);
action.setRedirectURL(current);

https://developer.servicenow.com/print_page.do?release=quebec&category=null&identifier=PDFGenerationAPIBothAPI&module=api