Using the Github UI to Make Pull Requests
From Joomla! Documentation
Revision as of 22:38, 20 October 2012 by Jmcameron (Mentioned joomla-cms to help searchers)
Github has a simple web interface that makes it very easy to propose a simple change to code. You do not need to install any software or do anything beside register for a git hub account.
These suggestions apply to forks of both joomla-cms and joomla-platform, although the screenshots are for joomla-cms.