From the last article, I hope you are now wondering “where do I get this awesome thing called S/MIME certificate!”, and the other kicker “What’s it going to cost me?” Well you are in luck because email certificates can be obtained for free! There are two site (that I know of) that provide free S/MIME email certificates: Instant SSL and Start SSL.
For this How To, I’m going to use Instant SSL. I have nothing against StartSSL (in fact they also give out free one year SSL website certificates!), but I find Instant’s process simpler and more direct.
Upon submitting your information, you should be forward to a page stating your “Application for Secure Email Certificate” is successful. Go check your email and wait for a message from InstantSSL (should be relatively quick), and click on the button that states “Click & Install Comodo Email Certificate”.
That is it! You now have a S/MIME certificate for signing and encrypting email messages. Stay tuned for using your newly acquired S/MIME email certificate in Apple Mail and in iOS.
Step One; Enter your name, email, key size, and revoke key
Step Two; Success! Now check your email
Step Three; Download, double-click and install in Keychain Access