Go to the issue tracker https://github.com/FXIhub/hummingbird/issues and create an issue/task/enhancement you would like to work on. Don't forget to label it appropriately. If the issue you want to work on exists already, you can skip this step. In any case, please assign yourself to the issue such that others can see it.
Go to your clone of the Hummingbird repository and create a new branch
git checkout -b issue/XX/description
with the issue number and a short description in the branch name.
Just commit (tip: use "Close #XX" inside the commit message for closing the issue with the final commit) and push your changes as usual
git push -u origin issue/XX/description
Make sure you have locally run the tests
py.test
before you continue to the next step.
You can create a pull request from your branch on the Github page: https://github.com/FXIhub/hummingbird/pull/new/master or
from the command line (if you have hub installed, e.g. by running brew install hub):
hub pull-request
Now your changes can be reviewed.
If you have the priviliges you can handle the pull-request using the Github page: https://github.com/FXIhub/hummingbird/pulls. Make sure that the issue branch is deleted again after the pull request has been merged.