how to edit the ~/.gvimrc.after and make modifications correctly?

how to edit the ~/.gvimrc.after and make modifications correctly?

I was looking to install a new theme to vim. So I found one that I liked
and was following along to the tutorial at
http://astonj.com/tech/vim-for-ruby-rails-and-a-sexy-theme/
it first had me install Janus. Then I downloaded the CodeSchool theme and
I was supposed to just put it in the .vim/colors. So I looked in there but
noticed that all the other theme were laid out differently, there were not
just .vim files, but theme_name/colors/theme_name.vim
So I created a similar layout. But then I was supposed to open
~/.gvimrc.after and paste in
color codeschool
set guifont=Monaco:h12
let g:NERDTreeWinPos = "right"
set guioptions-=T " Removes top toolbar
set guioptions-=r " Removes right hand scroll bar
set go-=L " Removes left hand scroll bar
autocmd User Rails let b:surround_{char2nr('-')} = "<% \r %>" " displays
<% %> correctly
:set cpoptions+=$ " puts a $ marker for the end of words/lines in cw/c$
commands
I only found a .gvimrc

It contained
if filereadable(expand("~/.gvimrc.before"))
source ~/.gvimrc.before
endif
" CtrlP OS-X Menu remapping
if janus#is_plugin_enabled('ctrlp') && has("gui_macvim")
macmenu &File.New\ Tab key=<D-S-t>
endif
if filereadable(expand("~/.gvimrc.after"))
source ~/.gvimrc.after
endif
So not really sure if this might be the file of the next step from here.