Select the Ellipsis (...) of the card that you want to created a Campaign for (Share your message with a Shuffle Campaign):
Select the "campaigns" option:
Select the Facebook messenger campaign that you have created:
Select "Copy Link"
Open your Facebook Messenger to the person/people you would like to share your campaign with. Place link and you will see a preview. Please note, it may take some time for your thumbnail to populate.
Please note, it may take some time for your thumbnail to populate. Please also be aware that if your thumbnail does not appear at preview, your thumbnail will appear upon selecting the "send" button: