advice about Csa please!!

Looking for some advice about Csa, is it hassle to sort that way? Basically I'm not with the baby's dad and he keeps saying he's supporting the baby but hasn't paid for anything so far, I'm 32 weeks and he'll ask if I need anything so I've said nappies and wipes and stuff and he'll say you don't need them yet, then says because I said no to money at the start of the pregnancy it's my fault.. So we were on the subject of him paying for the baby and he's adamant it's too much hassle going through Csa because they have to go through all of his pay slips and telling me we'll have to have a meeting with them (which even if we do have to it doesn't bother me)Just wondered if anyone can enlighten me on how it all works please?! Thank you!