Pretend you have a pack of cards in your hands and fan them out, then ask your mate to pick one. Of course there aren't any cards there so your mate will look a bit foolish. Ask him to look at it then ask him if it reminds him or her of their first sexual experience. Hopefully they will say not. Ask them to return the non existant card to the non existant pack, then fan them out again repeating the process. Again ask them if it reminds them of their first sexual experience. Again they should say no. Give them the pack of cards and ask them to shuffle them. As they shuffle them ask them if that reminds them of their first sexual experience.