step1: list the universities you want to apply from the website of Macleans.

http://www.macleans.ca/xta-doc/2000/11/20/Universities2000/index.shtml

step2: find the general addmission requirement for graduate school and the additonal requrement for department of CS.

step3: just follow the addimission instructions.

That's it. Quite simple.

step4: if you want making you application more competitive, try to contact the professores whose researches you are interested in.