COMPILE

If you are in a unix/linux environment, there is a Makefile.  Just cd to the top-level directory of the repo and run 'make'.
If you make changes to the included graphics you'll also need to update the 'figures' sub-directory.  Cd to giam/figures and 
recreate the Makefile using the 'fig4latex' script (then run make).

On other operating systems you can either install a development environment that includes TeX/LaTeX, fig2dev and (of course) make
(I've taken this approach successfully on a Mac) or just do things 'by hand'.  In particular if you want to make changes that only 
effect the text (as opposed to graphics), it is relatively easy.  Just download a LaTeX distribution, and use it to recompile GIAM.tex
in the top-level folder.

Also, consider submitting your changes as a pull-request.  Then your changes will shortly be available in the pre-compiled version.