This pops as soon as you complete an online battle as a new player, assuming that you find an opponent to play against. It doesn't matter whether you win or lose the battle.
On the menu choose 'Battle' then 'Online' and can select 'Ranked Match' next although other online battles may also qualify. Try selecting all regions and connection strength 1 for the best chance of finding an opponent. Finally choose your character and infinity surge options before the setup timer ends and the battle begins.