The megabounce is a hidden ability in the game, and you can use it in the game. Hold
to 'charge' your pogo bounce, and then let it go. When you're in the air, immediately hold
again to charge it, and when you hit the ground, release it. You'll know you've done a megabounce, because the character will twirl in the air without you pressing the A button, and you'll hear a celebratory sound effect. Simply do this for three Mega-Bounces without failure, and you'll get the achievement.
You can see this in action here: