To log in to Square, start by navigating to the Square website or opening the Square app on your device. Enter your registered email address and password in the login fields. If you have two-factor authentication enabled, you will be prompted to enter a verification code sent to your registered phone number or email. After entering the code, click “Sign In” to access your account. If you encounter issues, make sure your login credentials are correct and check for any service disruptions. For enhanced security, consider enabling biometric login options available on mobile devices.