To install the plugin issue:
easy_install pytest-figleaf # or pip install pytest-figleaf
and if you are using pip you can also uninstall:
pip uninstall pytest-figleaf
After installation you can simply type:
py.test --figleaf [...]
to enable figleaf coverage in your test run. A default ".figleaf" data file and "html" directory will be created. You can use command line options to control where data and html files are created.