Can I do it?

Yes!

How do I do it?

Select "People" from the course menu.
Click the "Add People" button.
Enter your colleague’s BTC email address in the "Add user(s) by" field.
Select an appropriate role from the "Role" drop-down menu.
Click "Next".
Confirm that the name is correct and click "Next".
Click "Add Users".

Keep in mind...

When it comes time for evaluations, students will be prompted to evaluate all users with the Instructor role in the course. The only user in an active course that is assigned the Instructor role should be the instructor of record for the class. If you would like your colleague to have the ability to edit the course, you can assign them the Reviewer role. The Reviewer role has the same permissions as the Instructor role, but will not trigger a student evaluation.

For more information, check out the Canvas guide on how to add users to a Canvas course.