You need to OI at the very beginning of 3 seconds, can be done with 9 seconds (Not with more or less). Hold forward until you start floating get ready to hit and hold fish before link's feet cross the line at the wall. After you have hit fish drop holding forward, and that's it. Too late on the window and you die early (back at fire), too early in the window (fire cs plays). It's slightly a bit different for > 5 seconds.