Do you speak any other languages?
But starting from English sh:
– for ś, move the middle of the tongue up, as with English y
– for sz, move the tongue back, so its tip is just behind the alveolar ridge
You can go either to Google Translate or ivona.com and experiment with random words containing ś or sz.
The differences are similar between ć and cz, ź and ż, and dź and dż.
Yes,my first language is Croatian,our alphabet is quite similar to that of the Czech,actually we took it as a model...
I think i understood it,but i'll try to experiment with some words,the difference to me seems quite subtle,especially in speech,when not so stressed.In croatian we only have Š.
Cz is like Czech Č (and our) if i am not mistaken,ć doesn't trouble me,we have the same letter.
Dź seems like our Dž,and dż like Đ,still trying to figure out ź vs ż
Well, if your dialect of Croatian distinguishes č and ć, then that's exactly that. Just try to extrapolate the difference between č and ć to sz and ś. Even if your č isn't retroflex, it's still better that nothing.
Of course I know that even if you can hear and pronounce a sound that is A+C, another that is B+D, and another that is B+C it's not always easy to hear and pronounce a sound that is A+D.