sudo apt-get install exuberant-ctags

Place in ~/.vim/plugin/tags.vim or in case of Pathogen:

cd ~/.vim/bundle

git clone https://github.com/szw/vim-tags.git

cd ~/.vim/bundle

git clone https://github.com/szw/vim-tags.git

In case of Vundle that would be:

Plugin 'szw/vim-tags'

Plugin 'szw/vim-tags'

placed in your .vimrc file