Improve/Update Documentation

[Michael Backus]

I'm a teacher that uses Arduinos in my classroom. I've put together some documentation for my class that explains how to install the software and drivers. I noticed the website is not entirely up-to-date. It's missing critical information on how to install Arduino on Yosemite and Windows 8. I'd like to add that information. How can I become a member capable of contributing such additions?