to ship two card is just put them in a envelope with a stamp and put it in out going mail it wont cost you at tops a quarter all you need is the winner of your auctions address, another thing you should do is when you going to take a picture set the cards on a table and put the camera as close as you can with out the picture going out of focus that way the person doesn't have to look up the card they can see it on your auction or put what it says on the card in the description of the auction basically if you can fit it in a envelope free shipping is the way to go with your auctions
It should cost you a stamp, but cards either way should be sent in a top loader or protected by something a little stiff to avoid damage. I been getting a good bit of cards of this site and there is a lot of people that think it is enough just to put it in an envelope and that has resulted in damaged cards.