How to write a VIM color scheme?

Question

I have been looking around for VIM color schemes and found some great ones out there (esp. by using http://code.google.com/p/vimcolorschemetest/), but I always want to change a

Answer 1

colorschemes are actually vim scripts. You use the hi command for coloring, which works like hi TextType guifg=#hexforegroundcolor guibg=#hexbgcolor gui=bold/italic/underlined/undercurled (assumed you use gvim). If you type :hionly, you get a complete list of text types with their current highlighting
see also http://vimdoc.sourceforge.net/htmldoc/syntax.html#:colorscheme