For this match you'll need to win a battle without taking ANY damage.
The easiest way to approach this is in VS Battle, under Free Battle mode. You'll want to choose Singles match and choose either 1p vs com, or 1p vs 2p. Now when selecting a character press Start to choose the battle settings. Select 10 seconds, max handicap (in your favor), and super easy, if you chose a com to verse.
As soon as the match starts use an Ult. Jutsu, throw shurikens, or use a Ninjutsu to get the 1 hit advantage on your opponent and then dodge him for the remaining time.