To do this cheat you must already have glide from getting your final lvl up to 3,5 or 7. Now you must find flat land(the place that I found was in the Under World, where Pain and Panic are). Now the next thing you do is jump into the air and press square. Do not press forward yet though because then you will have to start all over! Now that you have pressed square you chould just float down without going forward. once you have sunk all the way dont, meaning your not on the ground but still floating, you can finally press the forward button. As long as your on flat land you will fly forever!