Okay, here's a good trick that helped me remember when I was young:
In each of the first three sections there is a small amount of lava (or a lava pool as I like to call it) and the correct pipe is the first pipe after the lava pool. In the second section, you will need to hit an invisible block to get up. For the swimming part, just avoid the firebars, and in the last part, just avoid the hammer bro...he can be tricky!
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