If your tickets are Paperless Delivery, it means you must present the card used by the reseller to originally purchase the tickets from the venue or box office. Many events will only allow Paperless tickets as a delivery option for specific (generally premium) seats, or for the entire event.
When possible, the seller will purchase tickets on a Prepaid Gift Card. This card does not carry a balance, it is simply just the carrier of the ticket information, and can be discarded after the event. Using this method for entry is much like entering with a traditional ticket. You will present the card to the ticket attendant at the gate as you would with regular tickets, no need to go to the Box Office or Will Call.
Once the card is swiped, you will receive a small print out with your seat location from the ticket attendant. Since all of the tickets are on one card, your entire party must enter together.