I've written it in the video but just to recapture it.
You only have to smash some combos/do damage which isn't short, around 7 attack.
Repeat it until you gather all of the balls
Get level 7 of your KI bar.
Do another combo and at the end you can summon Shenron and choose.
WARNING: The enemy is also competing for the same requirements so if you gather all of them but he does the combo at level 7 he gets the wish.
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