Within Super Mario Odyssey, Mario has a number of jumps available to him that aids him in reaching certain areas along his journey. However, each of the these jumps will only see Mario cover much distance either vertically or horizontally, but not both.
If you find you need a little bit of a boost when jumping, follow these simple steps:
1) At the height of your jump, toss Cappy and hold down the Y Button.
2) Press ZL or ZR to have Mario flip to perform a Ground Pound.
3) As he flips, let go of the Y Button. After you do, quickly tap the Y Button and hold it again. As long as you are quick enough, Cappy will remain in position, allowing Mario to bounce off of him. This will allow Mario to then gain a new small jump, resetting him from his diving position.
4) Since Mario is longer diving, you can actually then throw Cappy once more should you need to change direction.
5) From here on out, you can repeat the process of turning a Ground Pound in a Dive to gain additional forward momentum.