Ah, I am part Asian and part European, so I have the ridiculous thickness of Asian hair (hairdressers always say OH MY GOD you have such thick hair! they freak out. like it's a toy.) mixed with the fine texture and sometime waviness of European hair.
It's a very dark brown/borderline black. In the past, I had it short (and subsequently felt like a boy) but now I've grown it out - mid back, heavily layered, side-swept bangs and I usually wear it blown out or wavy. I have to use Kerastase b/c it's basically the best shampoo ever made.
To answer the question about how to make hair consistently wavy, I use the Kerastase mousse - its in an orange bottle. The trick is to towel dry hair, brush through it, then muss it up with your fingers so it separates a bit. Then, leaning to the side, scrunch it upwards so its showing a wave. Then spray the mousse DIRECTLY onto the hair, and follow it with more scrunching. Make sure you don't put on too much... just about 4 squirts per head of hair. If you have really long hair, then use an extra 2 squirts on the ends....
Anyways, try that out and see how it is!