Knockout City

You don't even need to go into a Tutorial level to do this. You can do it from your hideout. Just grab the moonball and go over to the water tower on the map. Jump up and at the highest point, tap A to activate your glider and just glide around the outskirts of the map until it pops.

Once the achievement has popped, feel free to then fall to your death.

Go to your hideout. The easiest way to do this is to grab the moon ball and then use the jump next to your hideout. You can then scale the tower if you want to and jump off. Tap immediately to deploy your glider and just keep flying around the map until it pops. It's important to keep moving once your glider is deployed as floating while stationary makes you fall faster.

You can do this in the tutorial level that introduces the ball type. Begin to charge the ball as if you're going to throw it and then jump from the top of the map and instantly start to glide, making sure to hold the throw button as it will slow down your fall dramatically. From there just stay floating around until you almost hit the ground and then go off the map. Try to keep moving in a circle before hitting the kill zone.

Do not try to glide in place by holding the stick back, this will cause you to lose elevation faster then floating around naturally.

Here is a quick guide to getting it, can do it from the hideout