The source code to Insoshi is managed via Git, a version control system developed by Linus Torvalds to host the Linux kernel.
The first step is to install it from here:
http://git.or.cz/
The Git Guides also detail our recommended setup for your local repository: * Clone of the official repository git://github.com/pigfoot/mozbuilds.git
Our public Git repository is hosted on GitHub and can be viewed at
http://github.com/pigfoot/mozbuilds/
You can clone the the repository with the command
$ git clone git://github.com/pigfoot/mozbuilds.git
The clone make take a moment to complete.
Then make a local Git branch for yourself:
$ git checkout -b <local_branch>
where you should replace <local_branch> with the name of your choice (without angle brackets!).