From the Super Mario Wiki
The player starts out an a small Airship before jumping onto another Airship that a Warp Pipe that will warp them to a room with a Hammer Bro and two Boomerang Bros. After defeating them, a Warp Pipe will spawn that leads to another Airship that has a Hammer Bro and a Blokkablok on it.
After this Airship is another Airship that has two Boomerang Bros., a Blokkablok, the Checkpoint Flag and a Warp Pipe on it. The Warp Pipe leads to the Boom Boom battle, which takes place on two colored sections that have Spikes come out of them. After defeating Boom Boom a Warp Pipe appears that leads to an area that has three small platforms and several Donut Lifts on them. One of the small platforms contains a + Clock and after collecting it Pom Pom will appear. After defeating Pom Pom another Warp Pipe appears that leads to the Goal Pole.