Cloning this repository:

git clone git://gitorious.org/+mer/fremantle-hildon-desktop/hildon-theme-tools-mer.git hildon-theme-tools-mer
cd hildon-theme-tools-mer

Add this repository as a remote to an existing local repository:

git remote add hildon-theme-tools-mer git://gitorious.org/+mer/fremantle-hildon-desktop/hildon-theme-tools-mer.git
git fetch hildon-theme-tools-mer
git checkout -b my-local-tracking-branch hildon-theme-tools-mer/master_or_other_branch