the first corner I always just hit it straight in to test to see if they will bring their keeper out. I use top spin on all corners to make power and speed higher than normal too.
if they do and he reaches it I aim slightly further away or stick more power on it and use Guarin instead of Di Natale (Guarin's Power stat is insane) this way it makes me have a better chance of getting to it than the keeper.
if they don't I aim one touch inwards from the starting point and put half power into the cross with top spin, after that it depends on the player and who he is up against whether he gets it or not usually he will do (i will explain why in a bit) and then you header it towards the post there is nobody marking or has the most space.
i have found that the CB's when defending a corner are never near the 6 yard box, usually they are on the edge of the box, I have had times where I have won the header/punch and it's fallen to IF Miranda on the edge of the box who is now effectively leading my counter attack with just the ST in front of him at the halfway line.
EA are complete retards CB's should be the first line of defense for corners not outside or on the edge of the box, this is why it's so easy to score from corner's it's usually a full back or midfielder defending them.