Course registration for all general UCU courses takes place via Osiris. It is set up as a pre-enrolment procedure with several rounds in which you can enter your course preferences. A weighted placement process and possible draw will determine eventually for which courses you will be enrolled.
Your pre-registration reflects the discussion you had with your tutor about required courses and preferences. Semester pre-registration will open shortly after the midterm meetings.
Always make sure to prioritise all courses you must take. Also make sure that you choose enough alternatives (the system is designed to not give any disadvantage to people with sufficient alternatives). On the other hand: if complete registration is hampered by not entering enough alternatives, students may be enrolled in any course where there are places available to meet their required study load.
The deadline for course pre-registration is communicated in the academic calendar and also incorporated in the pre-enrolment module in Osiris. The Osiris course pre-registration manual can be found here.