How do I apply for Canadian Citizenship?

How do I apply for Canadian citizenship test?

Qualification Criteria
To request Canadian citizenship test you should:
Be more than 18 years old;
Give verification that you know how to talk and write in 1 of Canada's authority dialects (either English or French);
Be a Perpetual Inhabitant (PR);
Have lived in Canada as a PR for no less than 3 years out of the 4 years (1,095 days) just before the day you apply; and
Request Canadian citizenship test from inside Canada.