Genesis 3:2

"The woman said to the serpent, 'We may eat fruit from the trees in the garden,'"  Genesis 3:2

The first thing the woman does is try to correct the serpent, "Oh no, we can eat fruit from the garden's trees!"  But as it is pointed out in the Pulpit Commentary, that's her first mistake - entering into conversation with the serpent.  If you talk to the devil long enough, he'll convince you to see it his way, and for most of us, that doesn't take very long.