Memorize the application guide - then realize it can change at any time

Check for updates to the application process - rules/requirements can and do change, and the rules in effect when you submit your application are the ones that apply. New application guides can be posted, but you won't know unless you look.
Follow the checklist. Submit all required documents with the application. For some reason, lots of people don't. If English is your first language, it will be easier for you. Ask questions from CIC or here if there's something that is confusing.
If your work permit expires, make sure you renew on time, or depart Canada on time.
Fortunately, the CEC application is much simpler than most... Since there is no refund of the application fee, there's incentive to get it right the first time
