Developer Area/Release Instructions/Creating a GPG key
Follow these detailed instructions from Debian.
Once you're done, you can check that it works by running the
keycheck.sh script attached to this page (replacing 1234ABCD with your own keyid).
You may require to install gawk to run the script
sudo apt-get install gawk bash keycheck.sh 1234ABCD
And if it's all good, submit your key to the keyservers (replacing 1234ABCD with your own keyid):
gpg --keyserver pgp.net.nz --send-keys 1234ABCD