Here is the workflow for using Github for the non-committers who are developing their features on GitHub:

1. Create an account on GitHub.
   See Setting Up Git
2. Fork the Apache Repo:
3. Go to https://github.com/apache/incubator-cloudstack.
4. Click Fork.
   See Fork a Repo
5. Clone your fork:
   git clone https://github.com/<username>/incubator-cloudstack.git
6. Configure remote:
   git remote add upstream https://github.com/apache/incubator-cloudstack

Now, you are ready to go. You can pull the changes from upsteam, create branches, push the changes to origin.