Install and update vim plugins using pathogen from the command line.

vim-bundle install tpope/vim-rails

vim-bundle update scrooloose/nerdtree

vim-bundle list

Both install and update will take a github user followed by the repository name and install the master of that git repo into ~/.vim/bundle/. If you leave off the github username it will use the github mirror of vim-scripts' username.

Move vim-bundle into your PATH. Personally I add $HOME/.bin to my path and keep vim-bundle inside the .bin folder.