Clone a repo
Let's take hostmaster:
git clone http://git.drupalcode.org/project/hostmaster.git
If successful, you will have a hostmaster directory at the last state of development ('HEAD' in CVS speak, usually 'master' branch in git speak, though in our case this is now 6.x-1.x).
Check the status of the local git repository:
See the commit messages:
Check all 'releases'
Create a new branch for your local development:
git checkout -b <new_branch_name>
Create a new branch for development, based on an existing remote branch or tag
git checkout -b <new_branch_name> origin/<branch_name>