To create an organization, you simply need to sign up to Humio Cloud:
You have now created an account and an organization in Humio. Currently, you are the Organization Owner of the organization, and the only user in it. To invite more users to your organization, refer to the following section — Inviting users.
By adding users via their emails in User Management, you are inviting them to join your organization. You can navigate to User Management from main menu: Organization Settings > Users