(Re)move ~/.vim and ~/.vimrc if you have them already, and run:
git clone git@github.com:SideTour/vim-config.git ~/.vim
cd ~/.vim
git submodule update --init
ln -s ~/.vim/vimrc ~/.vimrc
Additional instructions for installing tmux-config related items here: https://github.com/SideTour/tmux-config/blob/master/README.md The submodule is already installed. Just add the symlink and bash profile line.
As long as your checkout is kept clean, you can easily update, rebase your local changes and update submodules with:
cd ~/.vim && git pull --rebase ; git submodule update ; cd -