Is there a "rule" here I don't know about? I quite like the look of a white collar folded up over top of a jacket collar, but I have a sneaking suspicion that I read/heard once that it looks tacky when you do that. I'm sort of new to dressing with a shirt and blazer, never having worked in an office setting (I've never owned a proper, office-appropriate suit), so maybe it's just that putting your shirt collar over your blazer collar is only inappropriate for formal business wear? Or maybe it's something that looks good for women but not for men? Or maybe I just imagined I heard that.