If you are being sponsored by your spouse, you need to do the medical before so it is submitted along with the application. If you are being sponsored by a relative or your application is skilled worker-based, you wait until CIC requests the medical. You need to contact the Designated Medical Practitioner who will be doing your medical to find out how they make these arrangements. Most persons generally have to make an appointment. You take along Appendix C of the Region Specific Form if you are being sponsored by your spouse.