I shoot ttf and ott the same. The only difference is that there is much less of natural flip when shooting ttf.
All in all I would say that just shooting with the exact same technique is all that is required, at least for me.
Bill Hays has some really good videos about his style of aiming. He shoots TTF I believe, and his philosophy of aiming and mechanics seems really sound. I'm afraid I don't know where the video is, so maybe someone can link it. You could check the Pocket Predator website or Youtube though.