I am a PGP beginner, having just downloaded GPG for OS X. I created my first pub/sec key for my email address and uploaded it to the public key server.
GPG has several features available, namely: 1) encrypt, 2) decrypt, 3) sign, and 4) verify. Given these options: What is the most secure way to use PGP to send & receive emails?
When sending, do I encrypt my emails? Or sign and encrypt? Or just sign? Which is best? And what is the difference between them?
What about receiving emails? What do you consider the most secure? If someone sends me an email, should I insist that it be signed? or encrypted? or something else?
There are many, conflicting explanations on blogs, tutorials, etc. for the best way to use PGP. I am looking for a "Plain English" explanation, geared towards non-InfoSec people like myself.
Note: I am not using the OS X Mail app, as I use a 3rd party email client (Sparrow).
Update: I am not interested in installing another email client. GPG comes with OS X Services menu items including encrypt, decrypt, sign, and verify. These will work with any application, email or otherwise. That is what I am using.