From the app.carbonregistry.com site, navigate to "Register" to provide details, i.e. email address and create a strong password for your account. Note you're responsible for keeping passwords strong and safe. You can also create a user account by using your Google, Microsoft or LinkedIn credentials for ease of managing passwords to log in. When ready click "Register".
You will be logged in to your user account and receive an email confirmation.
From your welcome screen you can complete creating your user profile and complete KYC.