These are the instructions if you just want to follow the latest nibabel source, but you don’t need to do any development for now.
The steps are:
From the command line:
git clone git://github.com/nipy/nibabel.git
You now have a copy of the code tree in the new nibabel directory.
From time to time you may want to pull down the latest code. Do this with:
cd nibabel
git pull
The tree in nibabel will now have the latest changes from the initial repository.