How does a mexican citizen become a canadian resident?

My friend asked me a question the other day that really just made me think. How does a Mexican citizen become a Canadian resident. Her visa is about to expire in the U.S. and she would like to know if she can try to become a canadian resident. We live in a small town where there are no immigration lawyers. She has contacted a few in other places but no reply. Help please. How would she do it?