The trick is amazingly simple, at the end of the game in the palace where you have to go up, you can skip taking the left and right paths, simply jump once holding ZR so Risky's hat parachute activates, giving you a little jump height boost when it opens, and then do the 3 well timed jumps using the Risky's cannon and at the end of the 3rd jump use the parachute again for that little jump boost and you'll make it to the platform above you each time and not have a need to take the left and right paths and you'll get to the final bosses room at the top.