This trick allows you to access Pianta Village without the rocket nozzle.
Get behind the Shine Gate in Delfino Plaza, and jump onto the first small wall. Face away from the gate, backflip (quickly press the opposite direction and jump) and hover over to the large Shine, and land on the little overhang surrounding it. Go to the edge facing the rest of the plaza, turn around, and do a triple jump, only make the first two jumps small. Do this next part quickly and carefully: on the peak of the third jump, hover, turn around, and grab on to the top of the gate. Jump into the pipe, and congrats! You've just gotten into Pianta Village without using the Rocket Nozzle!
In Gelato Beach, or any other levels where there are Bubbas (the big red fish that drags Mario underwater), you can stop them from draging Mario underwater if you pick up a piece of fruit and start swimming with it. The Bubbas will follow mario around (and sometimes even pass through him), but won't be able to drag him down.
In this episode, you're normally intended go complete the ridiculously long obstacle course on the back of the Ferris Wheel. However, if you look opposite the Ferris Wheel, there's a long, green platform. You can hover-jump from it across to the Ferris Wheel's top ledges, usually ignoring the hit detection with the spinning arms of the wheel. You can then just get under the top enemy and knock him off.
In this episode, you're meant to find an obscure way into the pool room on the top floor where the Shine Sprite is. Instead, grab a group of bananas and go up to that room's glass windows. Approach the windows and then turn facing away from them. Do a backwards jump to get right up against them, then do a double-jump. At the peak of your jump, throw the bananas and you should clip through into the pool room.
In this episode, enter the casino as intended. Jump onto one of the edges of the fountains most opposite the entrance to the room, Do a back-flip and hover towards the structure at the side of the room opposite the door and you should grab onto a ledge. Face to the side of there, hold L, and sidestep towards the black void on the other side for about 2 seconds. Then jump and hover in that direction for about a second and you should land on a platform with the pipe to the next portion of the level. It's a lot faster than hoping for those 777's!
In some levels you will see nails shooting up out of the ground. Jump on them, then ground pound them three times. You will ether get a free live or coin!
First, go to Delfino Plaza and collect 100 coins. Immediately after, find the pianta on a roof that throws you into a building for one coin. Collect the star inside the building and when you start over in Delfino Plaza, you will have 99 coins. Get another coin (to make 100) and you will get an extra life. Repeat as desired.
When you have finished the story, speak to the Pianta on the docks near the entrance to Ricco Harbor, and give him 10 coins. He will take you to the Delfino Airstrip.
Both of these items are given to you by the man wearing sunglasses.
You can get the Sunglasses by obtaining 30 shines.
You can get the Hawaiian Shirt after completing the game.