I use vundle now and found the following to be the easiest way to change your color scheme

set rtp+=~/.vim/bundle/Vundle.vim
    call vundle#begin()
             Plugin 'flazz/vim-colorschemes'
    call vundle#end()

    colorscheme molokai

You of course need to open vim and run :PluginInstall

And here is a preview of the schemes so you can pick your favorite