Submit bugs and send pull requests on Github. Any kind of contribution is welcome. if you're unsure or afraid of anything, just ask or submit the issue or pull request anyways.
Make sure you run tox before submitting code:
pip install tox
Run tox from the root of the project where tox.ini are located.
Run all actions defined in tox.ini:
tox
Tests are located in the tests folder using with pytest.
For Windows and OS X users, Vagrant can be useful unless you are developing for your current platform. This also makes sure you don't pollute your system with packages.