Joining an existing project is another way to get involved. Find a pre-existing open-source project in your field of interest by searching http://freshmeat.net or via a general web search. Most open-source projects are constantly evolving and need some kind of support. The details on joining vary for each project, but most projects have a web page outlining what kind of help is needed and how to get started.

Not the code-writing type? Then simply be a good open-source user. What does that mean? It means communicating. Bugs can't be fixed unless someone knows about them. Report bugs to the author or to the group maintaining that distribution of Linux (i.e. Red Hat or Debian). When reporting problems with software, please make your report constructive by including as much data as you can and being polite. Do you have a great idea for a feature or change? Tell the author of the package. The author can typically be found on the web or in the source code.