http://www.cic.gc.ca/english/information/applications/guides/EG7TOC.asp#eg76
Step 4: Mail the application
Note
Mailing instructions
Follow the instructions below to determine where to submit your application.
Put the completed forms, supporting documents required by the CIO and fee payment in a 23 cm x 30.5 cm (9″ x 12″) envelope.
Send your completed application to one of the addresses shown below.
Regular mail:
Affix sufficient postage (top right of the envelope)
Sender (top left of the envelope)
(Your name)
(Your Address)
(Your Postal Code)
Recipient (centre of the envelope)
Citizenship and Immigration Canada
Federal Skilled Worker
Centralized Intake Office
PO BOX 7500
Sydney, NS
B1P 0A9
Canada
Or by courier:
Affix sufficient postage (top right of the envelope)
Sender (top left of the envelope)
(Your name)
(Your Address)
(Your Postal Code)
Recipient (centre of the envelope)
Citizenship and Immigration Canada
Federal Skilled Worker
Centralized Intake Office
47-49 Dorchester Street
Sydney, NS
B1P 5Z2
Canada
Thanks