Avocado-VT is a compatibility plugin that lets you execute virtualization related tests (then known as virt-test), with all conveniences provided by Avocado.
First of all, make sure you have Avocado itself installed. You can check the Avocado online documentation at:
http://avocado-framework.readthedocs.org/en/latest/GetStartedGuide.html#installing-Avocado
The recommended way of installing Avocado-VT is through RPM packages. Documentation on how to install it can be found at:
http://avocado-vt.readthedocs.org/en/latest/GetStartedGuide.html