1. How do you get the red switch (where do you find it). 2. How do you..

1. (Vanilla dome water level) To get the red switch, go down the slope after the second dragon coin and jump to the left side of the gap. Move left until you reach a p switch. Carry the switch until you reach a solid wall of blocks. Activate the p switch, go through the wall and down the gap. Move left through the water until you find a key above you. Retrieve the key and carry it to the keyhole which is farther left. 2. (Donut Plains cave level) The green switch is in a green pipe before the second dragon coin. Get past the chargin' chucks until you reach a blue shell under some yellow blocks. Grab the shell and kick it up at the highest of four rotating blocks which were before the shell. A vine will come out, and go up it to find the key and keyhole.
3. (forest of illusion water level) After the fourth dragon coin, go down a vertical path and go left. Past a prize block with a mushroom and a sleeping fish, you will find a key and the keyhole. Good Luck!