learning

I wanted to know what's a correct or proper way pressing the clutch? I've been driven manual for a 2 week (new to standard) and while I was learning I have my heel on the mat then use my ankle. I notice my aunt bf does it different.. his heel is not touching the floor but using his whole leg...

my friend is teaching me how to drive stick and my parents are planning on buying me a civic soon since my little brother needs a car for college. my question is, how easy is it to learn stick and once i master / get the flow of things, should i get an SI?