You can connect your account when first logging in to the game. In case you started with a guest account and want to connect it later, please follow these steps:
- In-game, tap the Three Lines Menu:
- Tap the Cogwheel to open the Settings screen:
- Select the Account tab and tap the Connect Account button:
- Select what sign-in option to connect to - keep in mind that the connection is permanent and cannot be removed or transferred to another sign-in option:
Note: this account is already connected to Facebook, and can't connect to another sign-in option. The reward can still be claimed, though.