Generate keys

$ gpg --gen-key

Encryption

$ gpg --encrypt --sign --armor -r recipient_email -r my@email.com file_to_encrypt

Decrypt

$ gpg --output path/to/decrypted/file file_to_encrypt.asc

Create subkey

Backup files

$ umask 077; tar -cf $HOME/gnupg-backup.tar -C $HOME .gnupg

Find key and edit it

gpg --list-keys yourname gpg --edit-key gpg> addkey

Choose the "RSA (sign only)"

entropy stuff

gpg> save