I called Fedex and they said that I had to create an online account and schedule a shipment (and return shipment). It can't be done in the store. I filled out the forms online, printed off all the Fedex documents including the outbound and return labels, and took everything (Fedex docs, plus the passport copy, photos, Annex A doc) to Fedex and they took care of packaging the envelope and sending it out. There are several threads on canadavisa.com that discusses about what you need to do regarding sending a prepaid courier envelope from the US to Canada (it is a bit extensive and not at all intuitive). Hope this helps!