At the start of the level, cross the first spike bridge and hit the ?-Block to find a power-up (Super Bell). Continue across the next spike bridge, avoid the Parabones, and enter the Warp Box at the end. The camera will pan outward here, and you should see Green Star #1 on top of a pillar a little bit ahead. Navigate the spike bridges here, keeping an eye out for the Fire Bro on the opposite side. Head left of the Fire Bro and climb the little tower there to get the Green Star, then backtrack and continue forward.
The spike bridges here will move back and forth, plus you will have to contend with even more Parabones. The POW Blocks here might buy you some time away from the Parabones, but it will be brief, as they don’t defeat them for good. Dash across the second moving spike bridge, then jump in the Warp Box. This takes you to the Checkpoint Flag, and the next Warp Box will bring you to the following section, where the spikes will be moving. While the arrow is telling you to go right here, you know there’s going to be something off to the left, so head in that direction to find the Stamp at the end.
Return to the sign with the arrow and head in that direction now, stopping where you see the Fire Bro. The ?-Block here contains a power-up, which will be needed to climb the pillar behind it. At the top is a Mystery Box, bringing you to a bonus area with two walls. Climb the left one and hit the P-Switch, then quickly climb over to the right side to grab Green Star #2. Returning to the main level, continue right to the Warp Box and the next section. The large platform here will have a bunch of Parabones and the ?-Block on the opposite side contains a Super Star, so you can use it to clear the floor.
Once you’re done with that, turn your attention to the large moving platform of spikes and the donut blocks. Get on the moving platform and quickly jump to Green Star #3 on the other set of donut blocks. Swiftly get back on the moving platform, then get off on another one, which will bring you to a Warp Box. This will take you to the Goal Pole area, allowing you to finish.