You need to get a proper helmet fitting and insist on a carbon/titanium blend, lesser materials just won't do it. It's expensive, fitting and helmet approx £3k, but you know it makes sense. They don't actually offer any guarantees but, those of us in the know recognise that, nothing that expensive could be ineffectual.
But you don't want to look like a numpty so, once helmet is ready, you need to visit a quality hairdressers. They can cut and style your hair so that it fits smoothly into the vents on the helmet. Thus you can don, and remove, your new helmet, and your hairstyle remains unaltered.....simples