My hair is naturally messy - very thick, wavy in places but flat in others, a bit like a lion's mane. If I straighten it and use oil or serum it looks pretty good, and it has enough natural wave and volume that even straightened it doesn't look flat, just neat. If this is what my hair does best, I'll stick with it, but I do like that sleek but wavy, more relaxed look. How can I achieve it without a gazillion prodicts?