Instructors send announcements to students who previously excelled in the relevant courses, offering positions as Undergraduate Instructors for the upcoming semester. On the course website, there was a link to apply to positions for several courses in the department. The questions were basic and mainly checked for personal comfort in teaching the subject. After about a week, I received an email from my instructor with details for the position, and then met with him once on the first day of class to introduce myself face-to-face, although it was not necessary.