Faculty can add TAs and observers to their Canvas course:

Log in to Canvas and open your course. Click the People link in the left-hand navigation of your course page.

Syllabus, Files, People (highlighted), Pages, Quizzes

Then click the "+ People" button at the right.

Interface for adding People to Canvas, red arrow pointing to the "+ People" button.

Enter the student's email address. Make sure to use the short SAIC address, which is the first initial and first five letters of the last name, including any numbers if necessary. Using SAIC Gmail can help you find this address. Type the person’s name in the To: field when composing an email. You should see a list of possible addresses.

You can also use the ID number. Click the button next to "SIS ID" at the top, and then enter the ID number.

Add People interface, field for entering email addresses highlighted. Other options to select Login ID and SIS ID.

Select TA from the Role drop-down menu, and then click Next. (To add an observer, select Observer from the Role menu).

Red arrow pointing at TA in the Role dropdown, and a red arrow pointing at the Next button in the Add People interface.

On the next screen, it will list the TA's name and email address. Click Add Users.

Final screen in the Add People interface with the student's name and email address listed, and Add Users highlighted.

Your TA will receive an email notification that they have been added to the course. They can also find the notification and accept the invitation in Canvas.