1.go to practice mode
2.choose kirby and the computer to yoshi
3.choose final destination if you unlocked this stage
4.set the speed to 1/4
5.have kirby swallow yoshi make sure you put yoshi to human or you will miss your chanse
6.Have kirby press b to eat yoshi and watch the egg brake you will see yoshi is tiny keep doing this until yoshi is so small you can't even see him


note:yoshi will be back to normal if you reset or exit out of the practice battle