Cloning this repository:

git clone git://gitorious.org/themes/themes.git themes
cd themes

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

git remote add themes git://gitorious.org/themes/themes.git
git fetch themes
git checkout -b my-local-tracking-branch themes/master_or_other_branch

Cloning this repository:

git clone git://gitorious.org/~avatarchik/themes/avatarchiks-themes.git avatarchiks-themes
cd avatarchiks-themes

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

git remote add avatarchiks-themes git://gitorious.org/~avatarchik/themes/avatarchiks-themes.git
git fetch avatarchiks-themes
git checkout -b my-local-tracking-branch avatarchiks-themes/master_or_other_branch