>INSTALL THE ENIGMAIL PLUGIN FOR YOUR EMAIL PROGRAM
I Googled Enigmail as I was not familiar with it. It is "a security extension to Mozilla Thunderbird and Seamonkey." This seems incredibly shortsighted. Tons of people out there are on Outlook, Apple Mail, Gmail, etc. and not interested in Thunderbird.
There are other options, for example the surprisingly EXCELLENT gpgtools.org installer for Mac, which makes it super-easy to add signing and encrypt/decrypt and key management to OS X and Apple Mail. A quick Google reveals the nicely packaged gpg4win.org (I haven't used it). There's also Google's new Gmail GPG plugin (although yes it's beta) https://code.google.com/p/end-to-end/
I know this is the FSF, but I'd hope in the interest of defeating the surveillance state they could set aside dogma.
(Also, that page shouldn't default to the Linux options when I'm visiting from a Mac browser.)