*[Download and install](http://www.chromium.org/developers/how-tos/install-depot-tools) Chromium's [depot_tools](http://www.chromium.org/developers/how-tos/install-depot-tools)
and make sure it is in your path. We use the 'gclient' tool from depot_tools.
* If you haven't configured your machine with an SSH key that's shared by github then
follow the directions here: https://help.github.com/articles/generating-ssh-keys/.