gpg --full-generate-key;
Look for your Key ID in using the following command:
gpg --list-secret-keys --keyid-format LONG
Use the Key ID to get the Publick Key:
gpg --armor --export <GPG key ID>
If you need to export your private GPG key (to move to a different machine), use the following command:
gpg --export-secret-keys -a <GPG key ID>
To add a colaborator GPG public key you need first to import the key into your local key chain:
gpg --import gpg_public.key
See the ID of the new added key:
gpg --list-keys
Then add the key ID to the git crypt users
git-crypt add-gpg-user --trusted <GPG key ID>