When I try one, I always end up doing a 180 upside down or something like that. I don't do a straight flip. What am I doing wrong?

Try practicing on a trampoline first and make sure that you rotate fully. If you can do that a tantrum is almost the same. If that still does not help get detention from Shawn Murry.

you are probobly trying to look at the the water the whole time. in other words your not throwing your head straight back but back and to the side. try like chris said and practice on the trampoline even try doing backflips off the back of the boat to get used to spotting the water and throwing your head strait back

make sure that u change your edge when goin up the wake so the wake trips u. then u should be able to flip around staight

make sure that u change your edge when goin up the wake so the wake trips u. then u should be able to flip around staight