Сode contribution workflow

Find an open issue or create a new issue on issue tracker for the feature you want to contribute.
Fork the project on GitHub. You need to create a feature-branch for your work on your fork, as this way you be able to submit a pull request.
Make any necessary changes to the source code.
Add tests that verify that your contribution works as expected and modify existing tests if required.
Once your feature is complete, prepare the commit with appropriate message.
Create a pull request and wait for the users to review.
Once everything is done, your pull request gets merged.