If you are co-teaching on a module, you'll need to join that as a teacher so you can upload content and engage in collaborative activity with your students with teacher permissions.
To do this, login to app.talis.com and sign in using your institutional login details.
You will then arrive at the Module Manager
Click on the dropdown option and select 'Find Existing Module'
You'll then be able to select (and deselect) modules to join/leave from the list shown.
Once you have selected all the modules you wish to join, hit close. These with then appear on your module list via the drop-down in the Module Manager.
Please note, this will also enable you for weekly analytics updates via email, and email notifications based on your settings.