When you purchase a gift card you will receive an e-mail with the voucher code. You later use the code in the checkout to pay with. Note that the gift card is not a physical card but only an online card!
You can download the gift card and print it out if you wish to give it to someone. You will have to fill in the information yourself on the printed gift card. You find the download link in the product description.
The gift cards are valid for 1 year after you buy it and can only be used in the online store, not the physical stores in Como.