u/Konijnde

The next event's name, as well as Kiddy Kong's ability being water skipping suggests that the next event will be focused on Skip Groove, which scales based on the longest CONTINUOUS streak of water skips. You will probably need around 20 to get the million (depending on what else is available)

How to do water skips:

You want to be standing just inside the water, not swimming. Roll into the water, and jump each time you hit the surface. The timing on this is very precise, although the input can be buffered slightly (i.e. you can press a few frames too early), except on the first jump, as you will do a roll jump if you jump too early in that case. If you did it right, you will keep rolling. If you do a normal jump, you were too late. If you do no jump at all, you were too early.

If you have a turbo controller (or you can mash really fast) you can use it after the first skip to get an unlimited number of skips.