Use XSL style sheets to create reports from your ATML. If you are familiar with CSS (cascading style sheets) that are used to style HTTP, then you will quickly understand that XSL is for styling XML (ATML).
At the bottom of this page you will find two attachments that create a report from ATML. Download the ATML and XSL attachments into the same directory and then view the ATML in the browser. You will see the sample ATML Test Report as shown below.