If you use Vim 8 or Vim 7 with support for packages (echo has('packages') prints 1), I strongly recommend that you install MUcomplete as a package. Just clone this repo inside pack/*/start, e.g.,

mkdir -p ~/.vim/pack/bundle/start
cd ~/.vim/pack/bundle/start && \
git clone --depth 1 https://github.com/lifepillar/vim-mucomplete.git

Otherwise, use your preferred installation method. A few options are listed below.

Install apt-vim and run the following in terminal:

apt-vim install -y https://github.com/lifepillar/vim-mucomplete.git

Install vim-plug, then add the following to your .vimrc

Plug 'lifepillar/vim-mucomplete'

cd ~/.vim/bundle && \
git clone https://github.com/lifepillar/vim-mucomplete.git