What Makes Something 'Ita', in your Opinion?

I'm recently starting out with Lolita (I made my second Bodyline (all I can afford, sadly) order a few days ago, and when it arrives, I'll be all set!), and I'm really nervous about putting together bad coords. Can anyone give me any tips? I know to look out for bad lace, etc, but what in your mind ruins a coord?
:)