You have to give them the same email address you sign into paypal with, then they send the payment to that with their paypal account. it's pretty simple, but takes a little getting used to when you first start using it :) Most people have the winner send a message with payment that tells what their Listia name is and what they won and are paying for. That way it helps the seller keep things straight if they have many auctions going at the same time. :)