Chinese Mandarin "c" and "s" pin yin sounds?

i have that problem too. to me, it is all about context. sometimes you have to guess. c, sounds more like z, while z is a distinct buzzing sound. and then s is just more normal. i don't know how to explain it. sometimes when you are learning a new language, it is best not to let the little details get in the way and listen to how it flows instead.