they are randomly picked, but when you breed them, the mother picks three ivs to pass on and the father picks three more at random. so if you breed two flawless pokemon, the baby will be flawless (31/31/31/31/31/31)
no i dont sorry i just mostly have what i catch in the game i dont kno much of the whole iv bred thing, i thought iv's were just picked at random i didnt kno u could bred them like that but i would like to learn :D