Signature field is special
varnishing, which can allow certain fields to be written on. You have exactly the same writing field on the back of your credit/debit card.
*In case if you choose YES for
signature field, please note that signature field can be made only one side of
the card (usually back side of the card). Also, make sure that your signature is in rectangular
shape, color it with different color, than your card background (to be easily recognizable
that it is for signature field) and write in the comment section (left side of
the Designer page, last option in the tools column) that this is your signature