Install Key

Upload to OpenPGP

Export and upload the key to https://keys.openpgp.org. Then save the url to your card:

gpg --card-edit
gpg/card> admin
gpg/card> url
URL to retrieve public key: <paste the url to your public key>

Install card key on a new machine

gpg --edit-card
gpg/card> fetch
gpg/card> quit