There's two ways to do it! Instructions are below.
Via Microsoft Teams:
1. Install "Cyberday" app
2. Navigate to Organizations dashboard
3. Verify your identity
When you're the first user from your Teams domains, you will become the admin and the account creation will start. Creating the account takes a few minutes.
Via this website:
1. Click Free Trial -button and select the "Try browser version" -option
2. Create account and login with your email address or Google account
3. Fill in your organization details
This will start the account creation process, which takes a few minutes.