The default keys for folding are zaeither or zm(although zmI think it only closes the folds, and zatoggles them), so you should add the following lines to .vimrc:
set foldmethod=markerto enable collapse using markers ( {{{things in your code)
nnoremap <space> za, space, .
! , , autocmd s, :
autocmd FileType vim,c++,txt setlocal foldmethod=marker, , vim, ++ .
, , vim guru Steve Losh . , . .