I have been getting into speedrunning this game and am looking for help to achieve the stomp glitch on the gravity platform towards the start if the level

There are multiple plattforms you can perform this trick. So depending on which one you mean, the stick angle changes. Basically do this:

• Jump off the side of the plattform and try to stomp immediatly after clearing the railing.
• Hold the direction on your stick that you´re trying to jump to until you re flying.

Anything after that depends on which plattform you chose to do this from, which i can not help you with right now