- Your passport
- Two recent photos (passport size)
- Proof that you will return to your country (job, school, property, etc....)
- Provide proof that you have enough money for your visit to Canada (from your bank account or from the person who's inviting you)
- Letter of invitation
- Pay the fees (75$ single entry or 150$ multiple entries)
Check the website of the visa office responsible for the country or region where you live for more information on fees, including how to pay them.
The CIC website also says:
You may need to include other documents. These documents could be identification cards, proof of employment, a letter of invitation from relatives or friends in Canada, or a proposed itinerary. Check the website of the visa office responsible for the country or region where you live for more information.
http://www.cic.gc.ca/english/visit/apply-how.asp