There are many times we have contributors who want to contribute to Mozilla/Gaia, but we always would meet some new friends who are not so familiar with our working flows and Git.
In spite of keep telling them how to do that every time, I think it would be better to record screencasts about how to do that step by step. By following these instructions, you can easily jump into the ecosystem of Mozilla without too many obstacles.
Please fasten your seatbelt and let's start to hack :)