Hopefully this will show it a little better - with this hair I used the curved primitive shape a couple of times to get the curve in the hair for the top of the head - and then added on of the community vinyl twist shapes to get the flicks and curves. The three strands to the left is just to show how it builds up - it's really all about the masking and using the gradient shapes to hide where the hair strands start. Hopefully the pic is big enough, but you should be able to see some of the various strands and how I use the gradient shapes and also some of the tears shapes to build the hair up and help with masking the strands.
I used to work the same way in Forza 2 to 4, but really only found the curved primitive shape with the gradients effective - whoever came up with the community vinyls 3 and 4, big cheers as they are great for hair like this.
It's quite layer heavy initially, but you'll be able to get rid of a lot of layers later when you've built the hair up - some layers you just won't be able to see anymore and can get rid of them.
This hair is quite cartoon like in some ways, but doing this same thing would likely work for more realistic pictures too.