Actually, Apple has a pretty good explanation on this at:
When going through this information, please make sure you have your welcome email from dotCanada in front of you and refer to the paragraph under "Login Information".
A couple of tips:
Set-up up a POP email account.
Your incoming port should be 110, and your outgoing port should be 587 or 26 (your welcome email will have more detail).
Should the above link ever become broken, please let us know, and in the meantime, you can always go to Apple's homepage, and click on Support.