Tap the card on your phone, or scan its QR code. If the card hasn't been claimed yet you land on a screen headed Activate your card, showing the card's code, and it walks you through the rest - there's no app to install.

A card from a club, team or other organization

The screen says so - for example "This card was set up by a club. Set up your profile and it's yours." - and Set up my card comes first. Choose it and enter your name, email and mobile number. You don't need a code or anything else from whoever runs it: holding the card is enough. See "Somebody gave me a card from their club or team - how do I set it up?"

Any other card

You get a choice:

Create an account - the usual choice if the card is new and yours. You don't have to set a password: you can sign in afterwards with Google, or with a code sent to your phone. I already have an account - sign in, and the card joins your profile alongside any others you have.

If you also see I have an invite code, you don't need it - use one of the other two.

If you already have an account

Choose I already have an account. Once you're signed in the screen says Add this card to your account?, shows which account it's about to go to, and you confirm in one tap.

If it's an organization's card and your account isn't in one, you're asked whether to join that organization instead, with a list of what changes, before anything happens.

Afterwards

Once activated, tapping the card opens your profile. Every card linked to you is listed under My Cards in your dashboard.

If tapping opens somebody's profile instead of an activation screen, the card is already claimed - see "My card opens the wrong person's profile".