for ts 5's practice landing crossed up 180's (new front hand off handle). this gets you used to how you have to push the handle across your body to untwist that last 180. once you get to the peak of your height on your jump, pull really hard with both hands to your back hip, then spin fast and glue your chin to your front shoulder.
for a hs 5, you have to pitch over a little when you start to spin so you land over your toes. practice 180s like this... once you pop off the wake, take off your back hand, before you hit the water, grab with your back hand and spin it 180. thats what it will feel like for the last 180.
learning all your 180's switch and regular wouldnt hurt either.