Here a list of useful snippets, some are taken from sourcemage wiki as integration to the git tutorial, another useful guide is in the wine wiki
$ git clone git://live.polito.it/var/git/libnemesi
$ cd libnemesi
$ git branch sekrit
$ git checkout sekrit
#[hack... git commit hack ...]
#now publish it!
$ git push origin sekrit
$ git push origin :sekrit
$ git checkout --track -b local_name origin/remote_name