To use the git repo for working on this site:

1) install git on your computer (on a debian based system `apt-get install git-core`)
2) add a new user to gitolite, by adding their public ssh key to the keydir and their name to the repo in gitolite.conf.
3) git clone git@git.cinelerra-cv.org:www/cinelerra-site.git your-cin-site-copy

Make some changes, then 
git add newfile1.php newfile2.php
git commit -a -m "adding newfile 1 and 2"
git push

(There is a post-update hook which will automatically updates the site when you push.)

To update your local copy with changes others have made:
git pull
(or possibly git pull git@git.cinelerra-cv.org:www/cinelerra-site.git master)