If you are the company administrator for your Teachworks account and are also a teacher, you will need to create a teacher profile for yourself.
When creating the proifle, enter your name, email address, notification settings, etc. but leave the "Enable User Account" toggle switched to off. The reason for this is because you can log into Teachworks with your Company Administrator account.
You can find the steps for creating a teacher profile for yourself in this article: Adding Employees.