How do you complete world 5-3?

There are two comet pieces in this level, which you have probably figured out by now. To get this first one, you just avoid the mechanical Cheep Cheep and after you do this just let the water flow you through the finish line, in this case the comet piece. That's the first comet piece. To get the second one, you avoid the mechanical Cheep Cheep again and fall down the waterfall. After you fall down the waterfall you should notice a stream of water in the left direction. Move the logs, which Mario is standing on, to the left and follow this stream. (Please note if you don't to this right you will have to start the level over again and you will have to avoid the mechanical Cheep Cheep again, which is a burden.) Anyways now follow this new stream of water until you find that big wall on the right. Make sure you are a good distance away from this wall. Now press the y button and peel off that wall. Quickly press the y button again and stick the wall back in. Once you stick the wall back on, it's actually a pathway. Enter that pathway and you have your second comet piece, thus fully completing World 5-3.