I've searched through the boards and found the following suggestions. If anyone used other ways, please do let me know. Thank you.
- Flight itinerary for tentative return date
- Canadian bank account, property, etc.
- Proof of job searches (emails with recruiters, history of internet search)
- Proof of rental search
- Letter from family/friends that are willing to host us after returning
- Quotes for freight to Canada
- Notice periods required for current work/apartment ("Include the steps that are needed to leave the place where you are residing currently - how many months in advance you need to give notice for your work, or for the place you are renting etc.")
- Proof of discussion about return ("If you have been discussing coming back to Canada with family or friends, print out emails that show that.... etc! anything that proves that you have seriously started thinking about moving back")
- Letter of intent to return ("We included a signed covering letter that went through the steps my partner, the sponsor, had taken and will take once my PR is in place. They included job search (emails and names of websites used), Canadian bank account, property, e-mails with family and friends discussing our move, etc.")