This level will feature searchlights throughout it and if you get caught in one, then Bill Blasters will shoot Cat Bullet Bills at you (these will home on your position). Cross the first bridge and snag a power-up from the ?-Block (Super Leaf), then defeat the Hop-Chop up the steps to turn it into a springboard. Carry this across the bridge made of grey bricks, noting that the explosions from the Bullet Bills can destroy them. If the springboard starts to shake, that means the Hop-Chop will be turning back to normal shortly, so toss it on land to reset the timer for that.
When you get to the long bridge with the light moving left and right, you should be able to spot Green Star #1 in the air, so use the springboard to grab it. Continue through the stage until you get to the Checkpoint Flag, with the Stamp being above some ?-Blocks right after it. A little further ahead, you should see a cracked wall, so use the Bullet Bills fired from being spotted to break it open, revealing a Mystery Box. Inside the bonus room, you have 10 seconds to reach the top of the grey bricks and nab Green Star #2, noting that Bullet Bills will be fired at you constantly, so move fast before the “stairs” are destroyed.
Back outside, there will be a Red Ring just beyond the Mystery Box, where collecting the coins nets you a Super Leaf. The last section of this course will have you climbing a bunch of bricks and walls, while avoiding the searchlights. Along the way, you will find Green Star #3 encased inside some bricks. Use the searchlights and Bullet Bills to break them, collecting the star. Once you reach the very top, use the bricks to get to the top of the Goal Pole.