Linux : How to export public key for others/friends or your recipients

1) Login to your shell account

2) Use --export option to export your public key in text file
$ gpg --export –a > my.key
OR
$ gpg --export -a | mail -s "My key" friend@domain.com

Where
-a --armor : Create ASCII armored output.
--export : Export the key for sharing

First command write output to file my.key and second directly sends an email to your friend. Once my.key delivered to friend, he/she need to import it using the following command (aka adding keys to your keyring):
$ gpg --import my.key