This article explains how to create a teacher/admin account. If you're already in an organization, ask your organization's admin to invite you to the organization.
Head to https://app.opexams.com/ and click Sign up.
Select I'm a teacher.
Fill in you details including your name, email address, and password.
Click Sign up.
You will receive an email with a code to verify your email address. Enter the code in the box and click Submit.
Once you're in, select the features you're most interested in and click Continue. This helps us to know what to focus on in the future.
You can also easily log in with your Google or Microsoft account. Just click the icon of the method in the login page.