Enter an invitation code (either a friend’s $gointag or a code provided by Goin) in the app settings, under the "Referral code" section, within the first 7 days after installing the app.

Save at least €3 using the "Round up" method.

Once these conditions are met, you will automatically receive €3 in your Rewards wallet (if you were invited by a friend, they must also have saved at least €3 in round-ups).