Set the number of writes without committing before the message is shown:

let g:YUNOcommit_after = 20

With vundle add this to your vimrc, then relaunch vim and run :PluginInstall:

Plugin 'esneider/YUNOcommit.vim'

With pathogen do this, then relaunch vim:

cd ~/.vim/bundle
git clone https://github.com/esneider/YUNOcommit.vim.git

GArg ❤️ Git